Sonic the Hedgehog

"What you see is what you get! Just a guy who loves adventure. I'm Sonic the Hedgehog!"

- Sonic the Hedgehog

For other uses, see Sonic the Hedgehog (disambiguation).

Sonic the Hedgehog (ソニック・ザ・ヘッジホッグ) is the main protagonist of the Sonic the Hedgehog series and Sega's mascot. He is a 15 year old, blue, teenage, anthropomorphic American hedgehog, and is a laid-back and cool-headed character, meant to symbolize peace. Artist Naoto Ōshima, designer Hirokazu Yasuhara and programmer Yuji Naka are generally credited with the creation of the character. Like his name and species would imply, Sonic can move as faster than the speed of sound, has lightning reflexes to match (hence the name: Sonic), and can curl up into a ball (like a regular hedgehog), primarily to attack enemies. These are the distinguishing traits that were used to make his character and world-famous video games.

Concept and Creation
On April 1990, SEGA requested a game capable of selling over 1,000,000 copies, a character who could compete against Nintendo's Super Mario, and a character to replace Alex Kidd as the company's mascot. Several character designs were submitted by its AM8 research and development department. These included an armadillo (who was later developed into Mighty the Armadillo), a dog, a Theodore Roosevelt look-alike in pajamas (who was later used as the basis of Doctor Eggman's design), and a rabbit (who would use its extendable ears to collect objects, an idea that was later used for Ristar). Eventually, the mascot they selected was Naoto Ōshima's submission, a spiky teal hedgehog codenamed "Mr. Needlemouse", later renamed Sonic. Sonic's color was based on the SEGA logo, his shoe buckles based on Michael Jackson, his shoe color based on Santa Claus, and his personality was inspired by future-President Bill Clinton, who Ōhshima felt embodied a modern sensibility of wanting to get things done right away, righting wrongs as they presented themselves instead of letting them linger. Sonic was created without the ability to swim because of a mistaken assumption by Yuji Naka that all hedgehogs could not do so.

A group of fifteen started working on Sonic the Hedgehog and renamed themselves Sonic Team. The game's soundtrack was composed by Masato Nakamura of the band Dreams Come True. Sega sponsored the group's "Wonder 3" tour, painting Sonic on the tour bus, distributing pamphlets advertising the game, and having footage of the game broadcast above stage prior to its release.

The original concepts gave Sonic fangs and put him in a band with a human girlfriend named Madonna. However, a team from Sega of America, led by Madeline Schroeder, "softened" the character up for an American audience by removing those elements. This sparked a heated issue with Sonic Team. Naka later admitted that it was probably for the best. Sonic's precise age, weight, height and other physical characteristics vary depending on the continuity in which he appears and the style in which he is drawn. In the video games, Sonic's original design by Naoto Ōshima was with short spikes, a round body, one spike in his back, and no visible irises. Artwork featuring this design and drawn by Akira Watanabe was displayed on the package artwork for Sonic the Hedgehog (1991), and most subsequent Sonic video games featured similar designs. When Sonic the Hedgehog 2 for the Mega Drive appeared, Sonic's proportions changed. The original 1:2 head to height ratio changed to 1:2.5.

Beginning with Sonic Adventure in 1998, Sonic was redesigned by Yuji Uekawa as a 15-year-old character, with longer legs and a less spherical body, longer and more drooping spikes, two spikes in his back, and emerald-green-colored eyes. Further subtle changes to the character's design have been made in subsequent games. Spin-off media such as comics and cartoons have featured variations on all these video game designs, with restrictions set by the standardized model sheets.

Color
Sonic is blue in color in reference to SEGA's logo, which is also blue. Also, the color blue symbolizes peace, which Yuji Naka felt was appropriate for Sonic's heroic personality.

Early life
Nothing is known about Sonic's early life. It is unknown who his family is or if he has one, neither is it known how Sonic gained his trademark speed. All that is known is that Sonic was born on Christmas Island and that he has spend his life traveling the world, while searching for adventure.

At some point in his life Sonic met Dr. Ivo "Eggman" Robotnik and they became enemies under unknown circumstances, though it could very possibly be the fact that Robotnik is always looking to get more power to be ruler of any land he finds and knowing Sonic, he always chooses to help those in need. Since meeting with each other, Sonic fought Dr. Robotnik in a untold number of confrontations as the mad scientist attempted time and time again to conquer the world, with Sonic each time emerging victorious. Despite their many battles however, Sonic did not really account of his adversary.

Let the Games Begin
Sonic first recorded battle against his nemesis Doctor Robotnik was in the 1991 platform game Sonic the Hedgehog for the Mega Drive/Genesis. In the game, Sonic heard news about Robotnik attacking South Island after he had discovered that some powerful relics, called the Chaos Emeralds, were hidden on the island and so sought them to use their power to create weapons of mass destruction. Annoyed by Robotnik's perseverance, Sonic hurried to South Island to stop him.

Once Sonic arrived, he was met by Robotnik who revealed his new method to enslave the animal residents: by trapping them inside robotic shells, he could turn them into Badniks robots who would the follow his every command. This turn of events left Sonic greatly shocked.

Despite having the whole island as his enemy however, Sonic resolved to save the animals and get the Chaos Emeralds before Dr. Robotnik could get his hands on them. After traveling across the island while freeing the animal residents and gathering the Chaos Emeralds, Sonic entered the doctor's stronghold on the island and defeated the mad doctor and managed to drive him off the island. With Robotnik defeated, Sonic released the Chaos Emeralds in Green Hill and their power ensured the island's prosperity. After this adventure, Sonic became a well-known hero throughout the world.

Back With a Sidekick
In the 1992 sequel Sonic the Hedgehog 2 for the Sega Mega Drive, Sonic first performed his signature "Spin Attack" move. He also meet Miles "Tails" Prower, who would become Sonic's lifelong sidekick and best friend, for the first time.

Some time before the game, Sonic was traveling the world in his old airplane, the Tornado, in search of adventure. As his plane was reaching its limit however, Sonic discovers West Side Island and decides to land there. With nothing else to do, Sonic decides to relax and explore this new region. After a few days of exploring however, Sonic began to notice someone was following him and he saw that it was a young two-tailed fox called Tails, who had seen how fast Sonic could run and had come to idolize him. At first, Sonic was not particularly interested in the fox and left him alone. The young Tails continued to follow Sonic however, and Sonic came to be impressed by the young fox's determination and ability to keep up with him. As such, Sonic decided to let Tails tag along with him and they soon became the best of friends.

At the beginning of the game, Sonic was taking a nap under the Tornado, but he suddenly awoke to find something attacking West Side Island, and Sonic became enraged by this destruction. Believing that Dr. Robotnik was behind this, Sonic ran off to find the mad doctor.

It turned out that it was indeed Robotnik who was at his old schemes again. This time, he was turning the animal residents of West Side Island into his Badnik army to find the Chaos Emeralds, which was located on the island, to create his ultimate weapon, the Death Egg so that he could conquer the world. Accepting the challenge, Sonic headed off to stop Robotnik, get the Chaos Emeralds first and save the island, with Tails following him all the way.

When Sonic got all seven of the Chaos Emeralds, he discovered their powers can turn him into Super Sonic. Tails was at his side in most of the adventure and proved to be great assist to him, such as repairing Sonic's plane so they could board the Death Egg and destroy it. As they neared the Death Egg however, Sonic was forced to leave Tails behind when the Tornado, piloted by Tails, was shot down at the beginning of the Wing Fortress Zone, leaving Sonic by himself to fight Robotnik's secret weapon, Silver Sonic, on the Death Egg spaceship, followed by a gigantic robot in the image of the scientist himself. After Robotnik was defeated once again, Sonic escaped the exploding Death Egg and was caught by Tails in the repaired Tornado.

Escape from Eggman Island
In the arcade game SegaSonic the Hedgehog, Sonic was captured by Dr. Robotnik, along with Mighty the Armadillo and Ray the Flying Squirrel. Sonic teamed up with the other two and they traveled to escape Eggman Island, which was covered with traps.

In the end, Robotnik self-destructed the island, but Sonic, Ray and Mighty escaped just in time. However, the doctor had escaped once again.

Time Traveling Hedgehog
Sonic was solo once again for Sonic CD (1993), in which he went to Little Planet while it was near Sonic's home world once a year in order to explore it. However, his goals changed once he saw that the entire planet had been transformed it into a mechanical wasteland and chained to a nearby mountain, thus preventing it from leaving. After avoiding falling debri created by the massive chain, Sonic climbed the mountain and as he saw Dr. Robotnik's face carved into the mountain, he knew that his arch-nemesis was behind this and up to no good again. Climbing the large chain that held the planet down to Earth, Sonic traveled to the Little Planet with the intend of liberating it from the scientist's control.

As he arrived. Sonic learned he could undo Robotnik's work by using Little Planet's time passages to change the planet's past and by collecting the mystical Time Stones, Robotnik's reason for attacking the planet.

Shortly after his arrival, Sonic met a female hedgehog named Amy Rose, Sonic's biggest fan and want-to-be girlfriend, who was on the planet in hopes of meeting him. Sonic however, was far from excited to meet her and found her overwhelming interest in him annoying. However, only moments after Sonic met her, as they arrived at Collision Chaos, she was captured by Metal Sonic, the newest creation of Dr. Robotnik, which was build to outmatch Sonic in every way and defeat him for good. As Metal Sonic successfully escaped with Amy, Sonic now had the task of saving Amy as well. Using his unrivaled speed, Sonic managed to travel through time and ensure a good future for the Little Planet.

Near the end of his adventure, Sonic encountered Metal Sonic and the doctor once again, and had a race with his robotic counterpart on the Stardust Speedway and was victorious. In the ensuing victory of Sonic's, Robotnik accidentally damaged Metal Sonic severely which left him out of picture for the time being, and Sonic was able to save Amy from captivity.

Sonic went on and defeated the doctor in a final battle in the Metallic Madness. With his defeat however, the doctor's bases began exploding and were literally crumbling away, but Sonic managed to escape them and the Little Planet with Amy safely. After "seeing" to Amy's safety, Sonic stood in awe as the Little Planet went on to show Sonic's face in a shower of light as a sign of thanks to him before seemingly warping away from Sonic's planet, while leaving many new flowers growing around the area it floated above.

Robotnik, on the other hand, seemingly managed to sneak a Time Stone off the Little Planet, but Sonic spotted him and managed to put an end to his current schemes by using his Spin Dash to shoot a rock in the direction of his flying machine, causing it to explode. It is not known what happened with the Time Stone in question. After that, Sonic went on his adventuring ways around the world.

South Island in Chaos
In Sonic Chaos (also known as "Sonic & Tails" in Japan) for the Game Gear and Master System, Sonic and Tails were facing the threat of Dr. Robotnik sinking South Island by improperly using the Chaos Emeralds. Sonic and Tails collected the Emeralds before the doctor could, including the red one he already had in his possession and liberated the island of his control once more.

The Floating Isle and the Legendary Master Emerald
In Sonic the Hedgehog 3 and its expansion Sonic & Knuckles, both released in 1994 for the Sega Mega Drive/Genesis, Sonic meets Knuckles the Echidna for the first time, who would become one of his oldest rivals, as he sought to destroy the Death Egg once and for all.

The story starts with Sonic taking a nap at the beachside, until he is awoken by Tails who had discovered a large reaction of Chaos Energy out on the sea. At the same time, Sonic finds an ancient ring washed on shore, which makes him recall a legend he had heard about a floating Island in the sky with a highly unique culture that was supported by a powerful stone. Now filled with excitement, Sonic decided it was time for another adventure, and headed out with Tails in the Tornado to check out the reaction at sea.

When Sonic and Tails arrived at the location of the Chaos Energy reaction, they found the legendary Angel Island, the same island Sonic had thought of beforehanded. The duo soon noticed however that the island was kept at the ocean's surface and not flying in the sky where it belonged. To Sonic's surprise this was due to the impact of Death Egg's crash landing, which Sonic thought was destroyed after his adventure in Sonic the Hedgehog 2, but had actually just crash landed on the floating island and now was being rebuild. Not intending to let the Dr. Robotnik salvage and rebuild the Death Egg and use it to conquer the world, Sonic head out with Tails to stop Dr. Robotnik from relaunching the Death Egg.

As they neared the Island, Sonic used the Chaos Emeralds he had collected prior to the game to transform into his super form and storms the island. Shortly after arriving however, Sonic was ambushed by Knuckles the Echidna, the guardian of the floating island and its treasure, the powerful Master Emerald. The echidna, who had been tricked by Dr. Robotnik into believing that Sonic had come to steal the Master Emerald, somehow managed to force the Chaos Emeralds out of Sonic, and he returned to his normal form. After the loss of the emeralds, Sonic could only witness as Knuckles quickly snatched them and escapes to hide them, leaving Sonic and Tails forced to search the island for the emeralds.

Despite this setback, Sonic and Tails head out to to liberate the island from the control of Dr. Robotnik's robots and destroy the Death Egg for good. After a long struggle, Sonic and Tails makes it to the doctor's Launch Base, despite Knuckles many attempts to stop them, and the duo manage to defeat Robotnik just before the doctor could relaunch the Death Egg, making it crash into the Lava Reef Zone.

After the ordeal, Sonic safely lands with Tails' help in the Mushroom Hill. Annoyed that the Death Egg had survived yet another crash landing, Sonic knew it would not be long before the doctor tried to revive the Death Egg again and heads out with Tails once more to destroy it once and for all, while keeping Robotnik from using the Master Emerald as an eternal power source for it. Along the way, Sonic discovers the Chaos Emeralds' connection to the Master Emerald by witnessing them turn into Super Emeralds after exposure to the Master Emerald. Sonic also learns that these empowered emeralds allows him to become Hyper Sonic, an even stronger form of Super Sonic. After a long struggle, the heroic duo reached the Hidden Palace, where Sonic and Knuckles fought against each other for the first of many times to come. After his defeat at the hands of Sonic, the red echidna went to check on the status of the Master Emerald, which was kept here at the time.

After arriving too late, Knuckles realized he was being tricked by the mad scientist who told him that Sonic was the one after the Master Emerald, not Robotnik. After the doctor made his escape, Master Emerald in tow, Knuckles guided Sonic and Tails to a hidden teleportation device to the Sky Sanctuary, from which the trio could witness the successful launch of the Death Egg. However, the two had to leave Knuckles there as he was too exhausted from the previous two struggles. On their way through the Sanctuary, Sonic and Tails encountered two peculiar robots of the Eggman's; The Egg Robo, a robot in the image of Robotnik himself, and Mecha Sonic, the third robotic doppelganger of Sonic, which, during the first two encounters with the heroes, copied the behavior of the doctor as witnessed on two previous occasions. On their third encounter, however, the original managed to defeat the copy. The resulting explosion managed to make a tall pillar nearby crumble, but Sonic managed to get on the Death Egg by running along the pillar as it was crumbling to pieces just in time.

There, Sonic encountered Dr. Robotnik for the final showdown. He attacked him with a gigantic robot, loosely made in his own image, powered by the Master Emerald. Sonic managed to defeat the contraption which finally destroyed the Death Egg, but the doctor still had a trick up his sleeve, as he managed to steal the Master Emerald again using another battle suit. In order to pursuit him, Sonic transformed once again in his Super/Hyper Form, chasing the evil genius' across an orbit around the planet. After a long battle, Sonic emerged victorious, descending to Earth with the Master Emerald. In mid-flight, he powered down to his regular form, however, but was rescued by Tails, piloting the Tornado. The two then brought the Emerald back to where it belonged, Angel Island, allowing the island to float into the sky before leaving Knuckles for the time being.

Some time after this, Sonic, piloting the Tornado personally, rescued Knuckles after the latter's fight against the recently-reactivated Mecha Sonic from falling into the ocean. The two brought the Master Emerald back to Angel Island and the hedgehog and echidna parted ways once more.

Tough Trouble Times Three!
In Sonic Triple Trouble (also known as "Sonic & Tails 2" in Japan), Dr. Robotnik, in a failed attempt to create the ultimate weapon with the Chaos Emeralds, accidentally scatters the emeralds across the planet. As such, Sonic and Tails had to gather the Chaos Emeralds once more, before Dr. Robotnik could get his hands on them. However, this time, things got more difficult for the heroic duo when the doctor managed to trick Knuckles the Echidna into helping him once more. Furthermore, a dangerous treasure hunter by the name of Fang the Sniper also set his eyes on the mysterious gems, bent on stealing them for his own personal gain.

The heroes managed to race and battle their way through the world, getting the Emeralds before any of the others and confronted Fang in the mad scientist's base. However, the treasure hunter was scared away when the evil genius arrived with his newest contraption.

In the end, the machine was destroyed by the heroes, who then found Knuckles imprisoned by the doctor. They freed him and Sonic and Knuckles made up on good terms once more.

Slow Boots in the Labyrinth
In the 1995 game Sonic Labyrinth, Dr. Robotnik made one of his robots replace Sonic's shoes while the hero was sleeping in his home. After Sonic awoke, he realized that his shoes were not the same, for they were considerably heavier, disabling him from jumping or running at higher speeds. He tried to take these shoes off, but to avail as they were stuck to his feet.

Sonic then hears Robotnik boasting through his window that these new shoes could only be deactivated with the Chaos Emeralds' power, which he had obtained and hidden in his newly constructed super labyrinth on the South Island as his new base. Sonic soon realized however that he could still use his Spin Dash move and resolved to brave this labyrinth, stop the doctor and regain his speed.

Despite his new pair of slow-down shoes, Sonic made his way through the labyrinth, in the end defeating the mad scientist and regaining the Chaos Emeralds as well as his regular shoes.

The Fighting Tournament
In the 1996 game Sonic the Fighters (also known as Sonic Championship), Doctor Robotnik went on to build a second Death Egg, known as the Death Egg 2 and again announced plans for world conquest. Luckily, Tails had recently built a rocket that could fly it's pilot directly to the new Death Egg, however, it was only a one-seater and it needed Chaos Emeralds to take off. Therefore, they entered a battle tournament where the winner got to collect all the Chaos Emeralds, which was in the possession of all the participants.

In order to gather all of the Chaos Emeralds, Sonic had to fight many friends and foes, old and new: Knuckles, Amy, Bark the Polar Bear, future Team Chaotix member Espio the Chameleon, his friend Tails, Bean the Dynamite and the treasure hunter previously encountered known as Fang.

Before Sonic could be off to launch the rocket, however, the doctor showed up once again in a peculiarly familiar-looking spaceship. An unusual ray hit Sonic that knocked him out for a few seconds. When he came back to his senses, the doctor was gone and before him stood a near-identical copy of himself, the only difference being that the copy was completely monochrome. The hedgehogs fought, but in the end, the original hedgehog was victorious over his copy.Afterwards, Sonic headed back to Tails' workshop to launch the rocket, heading straight for the new Death

Egg. Upon his arrival, he was "welcomed" by a new Metal Sonic. The two fought a tough battle, but Sonic could turn the tide in the middle of the fight by using the Emeralds' power to transform into Super Sonic once more, defeating his mechanical doppelganger again. He was then facing the mad scientist himself, who built some sort of battle suit for himself in order to face Sonic. At the same time, it appeared that the station's self-destruct sequence had been initiated, leaving the two combatants under time-pressure. However, since Sonic was still in his super form, the mad scientist proved no match for him.

After having defeated Eggman, Super Sonic left the station in Tails' rocket, moments before it self-destructed.

Save the Flickies
On yet another adventure, Sonic traveled with Tails and Knuckles as they visit Flickies' Island, the eponymous island that is the main point of action in Sonic 3D Blast: Flickies' Island (also known as simply Sonic 3D and Sonic 3D Blast). Once the trio arrived however, Sonic discovered that Doctor Robotnik was at his evil schemes once more, as he had established a base on the island and was trapping the helpless Flickies resident so they power his robots and be used to find the Chaos Emeralds, which was located on the island.

Enraged by Robotnik's actions, Sonic decides to save the Flickies, return them to their home dimension and find the Chaos Emeralds before the doctor could get them. Sonic eventually managed to rescue all the Flickies on the island and, with the help of Tails and Knuckles, managed to gather all of the Chaos Emeralds before the doctor could do so himself.

With support from the rescued Flickies, Sonic managed to get to the secret lair of the mad scientist, where Sonic confronted him in a final, lengthy battle. Ultimately, Sonic emerged victorious and managed to escape the lair in time. With the island now liberated from the evil genius' control, the Flickies thanked Sonic for his help and peace reigned over the island once more.

Super Sonic Racing
In the prelude to the 1997 Sega Saturn and Windows game Sonic R, Sonic and Tails went on a relaxing vacation where they hoped to take a break from their adventures. As the two of them were strolling down the road however, they caught news about a racing competition. Despite Tails' urging, Sonic was not initially interested in a race as he knew he was the fastest. However, once he glimpsed at the list of registered participants, he saw Dr. Robotnik's name on the list as well. This caused a change of mind for Sonic, and he immediately ran off to register himself to the race. In the competition, Sonic had to face his friends Tails, Knuckles and Amy, as well as the scientist that was the reason for him joining in the first place. The evil genius planned to use Sonic to locate the Chaos Emeralds which were scattered around the race tracks and had brought with him robots to participate, both old and new: Metal Sonic and EggRobo, as well as Metal Knuckles and the ominous Tails Doll.

In the end, however, Sonic outraced them all and Dr. Robotnik did not get his hands on the Chaos Emeralds, proving himself once again as the fastest thing alive.

An Ancient Prophecy is Fulfilled
In Sonic's first true 3D Adventure Sonic Adventure (1998) for the Dreamcast, Sonic was put up against an ancient water monster named Chaos who was under control of Dr. Ivo Robotnik (Now named Eggman from then on). While enjoying himself, traveling through Station Square, Sonic saw human police forces fighting Chaos. Sonic stepped in and defeated Chaos, but it escaped through the drains, leaving Sonic without answers. The following day, Sonic woke up to see Tails' newest plane crash. After finding Tails, he revealed to Sonic that his new plane was powered by a Chaos Emerald. They then traveled to Tails' workshop, where Eggman showed up in the Egg Hornet, demanding the emerald, but they refused. As Sonic and Tails repeled the Egg Hornet, Eggman snatched the Chaos Emerald and revealed Chaos, who he transformed into Chaos 1. As Sonic recognized the creature from the day before, Dr. Eggman revealed to him that he plans to make Chaos invincible with all the Chaos Emeralds and then use it to build Robotnikland upon Station Square. The doctor then escaped.

Sonic and Tails then began collecting the Chaos Emeralds, before Dr. Eggman could give them to Chaos. After collecting the first two emeralds however, Dr. Eggman appeared and stole one of them. As they could not do anything about it, Sonic and Tails then went ahead to find the next one. However, they ran into Knuckles, who had been tricked into believing Sonic had stolen parts of the Master Emerald, and the two of them began fighting. During the fight, Sonic drops the two Chaos Emeralds, which is taken by Dr. Eggman who had appeared and gives them to Chaos 2, transforming it into Chaos 4. Despite it's increase in power, Sonic and the others still beat it and Eggman escaped in the Egg Carrier. Sonic and Tails tries to follow Dr. Eggman in the Tornado, but they are shot down. Sonic then landed in Station Square and hurries out to find Tails. He soon ran into Amy, who asks him to help her protect "Birdie", a bird she met earlier. Sonic is then dragged along for while, until Amy is kidnapped by ZERO, and Sonic chased after it.

After a brief chase, ZERO took Amy to the Egg Carrier. As Sonic's chase reached a dead end, Tails appeared in the Tornado 2, powered by another Chaos Emerald. Relieved to see Tails all right, they gave chase and managed to land on the Egg Carrier. After searching the Egg Carrier, Sonic found Amy, only to see Eggman take a Chaos Emerald from Birdie. Dr. Eggman then unleashed E-102 Gamma on Sonic while he escaped. Before Sonic can destroy Gamma however, Amy stops him. Sonic then told Tails to take Amy to safety, while he chased after Eggman on his own. Sonic eventually found Eggman, but also saw that Chaos had arrived too and had become Chaos 6. Big the Cat then arrived and points out that his friend Froggy was trapped inside Chaos, and Sonic promises that he will help save him. After helping Big save Froggy and fending off Chaos, Knuckles appeared and as Eggman tried to escape, Sonic left Chaos to Knuckles, while Sonic chased after Eggman. As Sonic ventured through the jungle, he came across a ruin where he is taken back in time to when Tikal and the shrine were under attack. He was then returned to the present, before Sonic could understand what happened. He then found Eggman and followed him into his main base, the Final Egg, and defeated him. As Eggman flew away, Sonic met up with Tails again, having seemingly saved the day.

After resting from all these ordeals, Sonic learned from Tails that Angel Island had fallen. As he arrives there, Sonic learns from Knuckles and Eggman that Chaos still lives and has rebelled against Eggman, and now has six Chaos Emeralds. As Sonic and Tails head out to find the last Chaos Emerald, Sonic is drawn into the past again. There he sees the Knuckles Clan's attack on the Alter, Tikal futile attempt to stop her clan and the event that drove Chaos to destroy the world in the beginning. As Sonic comes to Tikals aid, he witnesses Tikal sealing herself and Chaos inside the Master Emerald.

Sonic is returned to the present and heads out with Tails to find the last Chaos Emerald in the Tornado 2, but Chaos beats them to it and takes the Chaos Emerald before their eyes. Sonic then returns to Station Square which is being attacked by Perfect Chaos. As Perfect Chaos destroys the Egg Carrier 2, Tikal appears before Sonic, and explains that the sadness and anger Chaos felt from her clan's attack is the reason for its current destructive behavior. As Perfect Chaos releases the partially drained Chaos Emeralds, Tikal says they must seal Chaos again, but Sonic claims it would not work as Chaos would still be be full of rage if they just sealed it away again. Tails, Big, Amy and Knuckles then come to Sonic with all seven Chaos Emeralds, claiming that Sonic can still use their positive energies to stop Chaos. With everyone cheering him on, Sonic transforms into Super Sonic and defeats Perfect Chaos, while cleansing it of evil, thus returning it to a benevolent creature once more.

With Chaos and Tikal taking their leave and everything returning to normal, Sonic heads off, seeking out his next adventure.

Hedgehog of Dreams
In Sonic Shuffle (2000), Sonic was hanging out with Tails, Knuckles and Amy, until they were suddenly transported into Maginary World, a world created from the dreams of people in other dimensions. After a rough landing in the Temple of Light, the group began questioning where they were, while Sonic just called it a “very strange place”. There they met Lumina Flowlight, the person responsible for transporting them to Maginary World.

After introducing herself and the world to Sonic and the gang, she explained that she had called them here to help her save the Precioustone, the object that sustains Maginary World. Lumina explains that a person called Void had shattered the Precioustone and scattered its pieces to different part of Marginary World and had made their ruler and protector of the Precioustone, Illumina, vanish. Lumina also tells that she needs Sonic’s and the others’ help to recover the pieces of the Preciousstone, or Void’s darkness would spell the end of Marginary World. With everyone in agreement, Sonic willingly agrees to help Lumina save Maginary World, much to Lumina's joy.

The party then begins traveling to the different worlds inside Maginary World in order to recover the Precioustone pieces and restore the worlds affected by Void. Each time after collecting a Preciousstone piece, Sonic and the others have a vision where they see and interact with Void. While Sonic and the gang initially stand defiant against Void, they begin to see that Void shows signs of depression and loneliness which touches their hearts and they begin to think that there are more to Void than meets the eye.

After Sonic and his friends had collected all the Precioustone pieces and returned them to the Temple of Light, they heads back to the temple as Lumina sees Void heading there to seek out the Precioustone again. As Sonic, Lumina and the rest arrive at the temple to stop Void, Void claims he just want to become whole, but never could. As Sonic begins to see Void’s true nature, Void’s loneliness and despair reaches its peak and he transforms into a monster.

Sonic, Knuckles Tails and Amy eventually manage to defeat Void, but Lumina is lost in despair as the Precioustone was not recovering and begins to lose faith. They others however try to cheers up Lumina, and Sonic finds Void in the form of a dark gem. The group now understands that Void and Lumina embodies the positive and negative aspects of dreams and are two halves of the same being. Sonic then explains to Lumina that she should not reject Void as the despair and emptiness he embodies makes it possible for people to have dreams.

With everyone’s help, Lumina comes to understand that both positive and negative feelings are necessary for dreams to exist and Sonic hands Void over to Lumina, who now accepts Void. They then witness Lumina restoring the Precioustone and Lumina and Void returning to their original form, Illumina. As Marginary World is restored to an even better place, Sonic and the gang hears Illumina explaining that her own despair caused her to split into Lumina and Void to begin with. As she finish thanking them for their help, Sonic and the others return home to their own world.

You've Got the Wrong Hedgehog!
Dreamcast's Sonic Adventure 2 (2001) which celebrated the 10th anniversary of the series, introduced a new rival to Sonic, Shadow the Hedgehog. Shadow was released by Dr. Eggman to help in his plans of world domination, and in order to achieve that, Shadow began hunting down the Chaos Emeralds.

As Shadow robbed a federal reserve bank and stole a Chaos Emerald, everyone else mistook him for Sonic, and as a result, Sonic became wanted by the Guardian Units of Nations (G.U.N.). Sonic was eventually hunted down and captured by G.U.N. However, as they were transporting Sonic in a Military helicopter, he managed to escape.

After escaping G.U.N. and destroying a Bigfoot vehicle, Sonic meets Shadow who had just arrived at the scene with a Chaos Emerald. Realizing that he is the one behind the false accusations, Sonic demands an answer, but instead, Shadow demonstrates Chaos Control for Sonic and escapes his assault. Shadow then reveals his name and title to Sonic, before disappearing in flash of Chaos Control again and suddenly, Sonic finds himself surrounded by G.U.N. soldiers and is arrested once more.

Sonic is brought to Prison Island where he is locked up. Luckily, the following day, Tails and Amy arrives to break him out. After Amy frees Sonic from his cell, he learns that Shadow was on the Island and that he was working with Dr. Eggman, which leads to him running off. After a while, Sonic finds Shadow and they have a brief battle, but is interrupted when they learn that the Island is about to explode. Sonic manages to escape the Island with Tails and Amy just before it explodes.

Back on the main land, Sonic and the others sees Eggman's broadcast where he reveals the Space Colony ARK and displays the Eclipse Cannon by blowing up half of the moon, and demands total world control within 24 hours or he would fire the cannon on the Earth. Sonic realizes that had to be the reason that Eggman had been collecting Chaos Emeralds. Tails begins to plan how to track Eggman down, but the police arrives and Sonic leads them away. Sonic is then contacted by Tails who says he can use the President's limo to trace Eggmans signal. They two of them meet up there where Sonic tells the President that they got it covered and finds out that Eggman is on board the ARK.

With the help from Knuckles, Sonic, Tails and Amy find Eggman's base, hoping to find a space ship that can take them to the ARK. While they manage to enter the base, Eggman appears and unleashes the Egg Golem. Sonic manages to stop it and joins the others in a space ship, just before liftoff.

After a crash landing on the ARK, Sonic plans to destroy the Eclipse Cannon. Tails gives Sonic a fake Chaos Emerald that he can use to destroy the cannon from the inside out. Before Sonic can insert the fake emerald into the cannon however, he is contacted by Dr. Eggman. He demands that Sonic hands over the final Chaos Emerald, or he would kill Amy. Sonic thought he could trick Eggman into taking the fake emerald, but Eggman saw through this, captured Sonic in a capsule and ejected it into space. Before the capsule could explode however, Sonic managed to use Chaos Control with the fake emerald and sends himself back on board the ARK. As Sonic heads to destroy the cannon with the fake emerald, he meets Shadow again and they shared a final battle. After Sonic wins, he managed to destroy the Eclipse Cannon just before it fired.

As Sonic returns to the ARK, he and all the others witnesses a recording of Gerald Robotnik that tells the world that the ARK would crash into the planet, wiping out the human race as his revenge at the world for the death of his granddaughter, Maria. They then came up with plan of using the Master Emerald to deactivate the cannon's core, powered by the seven Chaos Emeralds, to stop the Space Colony's crash course, which Sonic tells them to leave it to him.

With everyone working together, Sonic and Knuckles made it to the core, but are then intercepted by the Biolizard. Suddenly, Shadow shows up and holds off the Biolizard while Sonic and Knuckles deactivates the Chaos Emeralds. Instead however, the Biolizard teleports outside the ARK and merges with the ARK, thus becoming the Finalhazard and keeps the ARK on its collision course. Determined to stop this catastrophe, Sonic and Shadow uses the Chaos Emeralds to become Super Sonic and Super Shadow, and together they defeat the Finalhazard. The duo then stops the ARK by sending it back into orbit with a massive Chaos Control, but Shadow runs out of energy from the effort and falls into the atmosphere, and was presumed dead, while Sonic survived. As Sonic came back on board, he only brought them his Inhibitor Ring and assured them that Shadow was a great hero that he would never forget. As the rest of the gang returned to the Earth, Sonic bid farewell to his worthy opponent and team mate.

In the game he has many unlockable costumes for the multiplayer mode

Back to Protecting the Emeralds
After the 1999 game Sonic Pocket Adventure, Sonic returned to the handheld games with Sonic Advance (2002) where Sonic, Tails, Knuckles and Amy went back to their adventures fighting Dr. Eggman in 2D side-scrolling levels, as the doctor resumed his hunt for the Chaos Emeralds. In the end, Sonic and his friends collects the Chaos Emeralds first and Sonic uses them to become Super Sonic to confront Dr. Eggman on the moon and defeats him. After the fight, Sonic seemly disappears, but then reappears a few days later (stil in his super form) as he flies through the sky.

Sonic to the Rescue
In Sonic Advance 2, Dr. Eggman kidnaps Tails and Knuckles as he attempted once more to build the Eggman Empire, but once Sonic learned about his friends kidnappings, he immediately heads out to save them. Along the way, Sonic encounters Cream the Rabbit and Cheese the Chao for the first time, who were held hostage by Dr. Eggman. Sonic however, managed to save Cream and Cheese and was amazed by the young girl's manners when she thanked him. They would then join Sonic on his adventure as Eggman had kidnapped Cream's mother, Vanilla the Rabbit, too and they wanted to save her. Shortly after, Sonic rescued Tails from Eggman too and confronted Knuckles who was tricked by Eggman again to fight Sonic and joined them on their adventure fighting Dr. Eggman. After seemingly beating Eggman, Cream finds her mother, only to have her kidnapped by Eggman again. Seeing Cream cry at the loss of her mother, Sonic transforms into Super Sonic and saves Vanilla. After the battle, Sonic reunites Cream and her mother, but he does not stay for long and runs off again, looking for a new adventure.

An Old Friend, a New Enemy
The final Sonic Advance was Sonic Advance 3 (2004). While hanging out with Tails, Sonic witnesses Dr. Eggman splitting the Earth apart with Chaos Control. Sonic then immediately heads out with Tails to stop Dr. Eggman, restore the world and collect the Chaos Emeralds before Eggman can use them to build his empire. Along the way Sonic also faces Dr. Eggmans newest creation, Gemerl, a rebuilt version of Sonic's old friend Emerl, on several occasions. After beating Eggman and Gemerl at the Emerald Altar, Sonic and his friends uses the Master Emerald to restore the world. Shortly after their defeat, however, Gemerl betrays Eggman, takes the Chaos Emeralds from Sonic and transforms into a robot-like orb. Sonic then transforms into Super Sonic and is joined up by Eggman and together they defeat Gemerl. After the battle Sonic passes out, but wakes up and finds himself surrounded by his friends who had awaited his return. After seeing Eggman leaving, Sonic then heads out himself, searching for new adventures.

An Old Rival's Deadly Return
A third 3D action game, Sonic Heroes (2003) was the first multi-platform release for Sonic. It featured four different teams made up by three characters in each, and marked the official return of supporting characters Team Chaotix as the teams battled Eggman. The story for Sonic begins with him running around on his own, until Tails and Knuckles comes flying in the Tornado. Tails reveals that Dr. Eggman had sent them a letter, where he claimed to have created "the ultimate weapon" and that he challenges Sonic, Tails and Knuckles to stop him within three days time. Sonic, confident as ever, sees this as an invitation to a "party", and says that he would not miss this challenge for anything. He then heads out with Tails and Knuckles right behind him, officially forming Team Sonic.

Sonic and the gang begin their quest by tracking down Dr. Eggman, and encounters him on a few occasions, but along the way they come across Team Rose and Amy. After fighting and escaping Team Rose, Team Sonic follow Dr. Eggman to the Bullet Station, where they fought him in the Egg Albatross, just before running out of their three day time limit. It was then revealed that the Eggman they had been chasing was a fake and that their challenge letter was merely a distraction, while Dr. Eggman prepared his Egg Fleet for launch. Enraged, Sonic runs off in hot pursuit of Dr. Eggman with Tails and Knuckles following behind. Along the way, they have a brief confrontation with Team Dark, where Sonic, Tails and Knuckles learn that Shadow was still alive. After traveling through the Egg Fleet, Team Sonic makes it to the Final Fortress where they fought Eggman in the Egg Emperor and won.

After heavily destroying the Egg Fleet, Knuckles mentioned it was a close one this time, but Sonic said otherwise. Knuckles then tries to tease Sonic with the fact that he would not have made this on his own, but to his amazement, Sonic agrees. Shortly after the heroes witness the return of Metal Sonic (In his Neo Metal Sonic form) who has been the one staging Team Sonic's and the other teams adventures and impersonating Eggman, so that he could follow each team and copy their data in a master plan to achieve world domination himself. Neo Metal Sonic then underwent a massive transformation into Metal Madness. After seeing that the teams had collected all the Chaos Emeralds, the real Dr. Eggman comes up with the plan of using them against Metal Sonic. Though their chances of wining was slim, Sonic volunteered to go up against Metal Sonic alone, but Tails and Knuckles insist on going with him, while the other teams would buy them some time, which Sonic accepts. Team Rose, Team Chaotix and Team Dark then fought Metal Madness to give Sonic time to charge the Chaos Emeralds.

When they were ready, Metal Madness assumed his ultimate form, Metal Overlord and took off. Sonic then turned into Super Sonic, while granting Tails and Knuckles Super Shields, and they chased after Metal Overlord and defeats him, causing him to revert back to his original form. Metal Sonic questioned why he could never defeat Sonic who told his metallic counterpart that he would be ready for a rematch anytime, before searching for his next adventure.

Black Invaders
In Shadow the Hedgehog (2005), Sonic worked with most of the cast from Sonic Heroes and G.U.N. forces to repel the Black Arms invasion of Earth. He appears often during Shadow's Hero Missions where he helps Shadow in his fight against the Black Arms and their leader, Black Doom. During some of their missions, Sonic shows concern for Shadow's amnesia and tries to help Shadow recall event from their adventures in Sonic Adventure 2. Depending on the player's choices, Sonic becomes either an ally or opponent in the game's pre-final boss; if Shadow completes the Hero Mission in Final Haunt, Sonic will assist Shadow in his fight against Black Doom, and if Shadow completes the Dark Mission in Black Comet, GUN Fortress or Final Haunt, Sonic will team up with Diablon to stop Shadow from assisting the Black Arms, but is utterly defeated and Shadow takes the final Chaos Emerald.

In the last story, Sonic arrives with Tails, Knuckles, Amy, Rouge and Dr. Eggman to stop Shadow from giving Black Doom the Chaos Emeralds and he tells Shadow to give the emeralds to him. Black Doom however, takes the emeralds and uses an enhanced Chaos Control to transport the Black Comet to the surface, something which Sonic instantly recognizes. Sonic and the others then intended to stop Black Doom, but they all soon fall prey to a nerve gas, which leaves them paralyzed and Black Doom unleashes Death leeches to prey on them. Shadow however, proved to be immune to the gas and he persued Black Doom. As he left, Sonic told Shadow that he was their only hope left.

Sonic and the others eventually managed to escape the Black Comet and cheered Super Shadow on as he fought and defeated Devil Doom. He then witnessed Super Shadow sending the Black Comet back into space and blewing it to pieces with the fully charged Eclipse Cannon. With Shadow having saved the world, Sonic was left rather impressed by the black hedgehog, claiming it was "sweet", and joins the others for a laugh as an enraged Knuckles chases Eggman around.

Fighting, Friendship, and "Fatherhood"
In 2003, Sonic Battle came out for the Game Boy Advance. This time, Sonic and his friends work together to raise an ancient and all-powerful robot and protect it from Dr. Eggman who wants to use it for global domination. During the adventure, the robot, later named Emerl, would come to see Sonic as a father-figure.

While on a boring stroll, Sonic finds a robot called the Gizoid lying on the beach. As Sonic examines it, it starts to move. It tells Sonic to show his power, and Sonic displays some fighting moves, thus it forms a Link with him. Sonic then decides to take it to Tails to get it examined, but he runs into Shadow who demands that Sonic hands over the Gizoid, but he refuses. After defeating Shadow, Shadow tells Sonic to keep it from Eggman and leaves. As Sonic wonders about where Eggman fits in all this, Tails arrives and they take the robot to Tails’ Lab. On his way, Sonic meets Rouge who wants to team up with Sonic so that she can have the Gizoid, but she leaves after Sonic beats her in a fight. When arriving at Tails’ Lab, Sonic encounters an E-121 Phi and defeats it. Worried that Tails could be hurt, Sonic hurries to the lab and luckily finds Tails unharmed. Tails then reveals to Sonic that the Gizoid develops with each Chaos Emerald inserted into it and it can copy fighting moves. Thrilled by these revelations, Sonic decides to train it. After some training, Sonic and Tails decides to go see if Knuckles has a Chaos Emerald and Sonic decides to name the robot Emerl. On the way they are attacked by Chaos Gamma which Sonic mistakes for Gamma, but they defeat it. When they arrive at Knuckles’, Knuckles mistakes Emerl for a Phi and tries to attack him. Sonic tries to explain the situation to Knuckles, but to no avail. After Emerl defeats Knuckles, Sonic receives his Chaos Emerald and they insert it into Emerl, who thanks Sonic afterwards and calls out for more battles, much to Sonic’s amazement.

Sonic continued training Emerl for a while, until Tails decided to take Emerl to Central City to fully examine him. When they return, Sonic learns from Tails and Rouge that Emerl is a weapon of mass destruction, which is the reason why Eggman wants him, but Sonic refused to believe it. Sonic suggested they could reprogram him, and Rouge says that they can reset Emerl by inserting all seven Chaos Emeralds into him and give him an unknown keyword. Sonic questions Rouge why she is helping them, and she answers that it is the best for the world (and herself) that Eggman did not get a hold of Emerl. Rouge then makes Sonic introduce her to Emerl by making him form a Link with her, but then suddenly leaves.

Sonic continues Emerl's training, but it is cut short when he sees Amy coming and runs away. He later returns and learns that Rouge had stolen Emerl, due to the earlier Link he formed with her. Sonic soon after finds Emerl with Rouge however, and engages her in battle, intending to protect Emerl and get him back. Rouge eventually surrenders Emerl to Sonic, as she thinks Emerl is more trouble than he is worth. After leaving for a while, Sonic learns that Emerl had been training with Knuckles and that Knuckles had been tricked by Eggman again.

Later on, Sonic and Emerl is approached by Amy again, who views Emerl as hers and Sonic’s “baby”. As Sonic faces Amy’s wrath about how Sonic has been raising Emerl, Emerl makes a bad choice of words and Sonic immediately runs off. He later returns to find Emerl with Amy, and she tells Sonic that he has no excuse for marrying her now, since she had helped raising Emerl. Sonic then tells Amy to close her eyes, but runs off once more once she closes them.

Sonic and Tails later leaves Emerl in Amy's and Cream’s care, as the two of them check out a lead on a Chaos Emerald, which turns out to be fake. Sonic is then contacted by Eggman who said that he held Cream and Emerl hostage, but because the two of them had escaped, Sonic did not believe him. He soon after sees Eggman captured in his own trap by Emerl and Cream on-screen, and heads out to pick the pair up.

Sonic is later approached by Shadow again. Sonic thinks that Shadow is here to capture Emerl, but it is not his intention. Shadow says that Emerl is close to awakening his full power, as he only needs one more Chaos Emerald and that he could bring the end of the world. Sonic, however, believes that Emerl would not do that, as he has a heart and explains that there is a way to reset Emerl, but Shadow merely brushes Sonic’s speech off. Sonic then gives up on trying to convince Shadow and lets him have Emerl, who just arrives, having been attracted by Shadow’s Chaos Emerald and Shadow restates his statement. Unshaken by this, Sonic lets Emerl go with Shadow, believing he will learn who he really is with Shadow’s help.

After being reset, Emerl comes to fight Shadow. However, Sonic arrives to give Emerl more of a challenge. After the fight, Emerl thanks Sonic and Shadow for all their help. Having seen that Emerl no longer needs him, Sonic tells Emerl to live his life to fullest on his own, but not before he tells him that his punches need some work.

Later, Sonic witnesses Eggman revealing the Death Egg with its Final Egg Blaster. The heroes decide to stop him, but since only one of them could be sent to the Death Egg and stop Eggman, Sonic suggested that Emerl should go, which he accepted.

Sonic witnesses Emerl defeating Eggman, but then Eggman fires the Final Egg Blaster and destroys some stars: This great display of power caused Emerl to revert to his original programming and Eggman tries to assume control over Emerl, but he knocks Eggman away and prepares to fire the Final Egg Blaster on the Earth. In order to stop Emerl, Sonic travels to the Death Egg with the Master Emerald, hoping to negate the Chaos Emeralds energizing inside of him, but Emerl smashes the Master Emerald upon seeing its light. Tails then tells Sonic that he can reverse Emerl’s programming by inflicting enough damage on Emerl, but it would destroy him in the process. Seeing no other choice, Sonic, with a heavy heart, engages Emerl in a high speed battle. Seeing the overwhelming strength of Ultimate Emerl, Sonic decides to fight at his full power and defeats the all-powerful Gizoid.

As he begins to break down, Emerl thanks Sonic and his friends for everything, but, in a rare chase of visual sadness, Sonic tries to assure Emerl that everything would be fine, but to no avail and Emerl disappears before Sonic’s eyes. Sonic then returns to the Earth and as he sees Cream crying over Emerl’s death, Sonic tells Cream that Emerl was still with them in the Emerald Shards. As Tails wonders if they would ever see Emerl again, Sonic assures them positively that they would.

Fast Flyers
In Sonic Riders (2006), Team Sonic find themselves in Future City, as they search for a Chaos Emerald, but suddenly a group of thieves on Extreme Gear, called the Babylon Rogues, reveal themselves. Tails sees that the emerald is in their possession and Sonic runs off to intercept them. After Knuckles manages to knock Storm off his Gear, Sonic grabs his Gear and decides to give chase to the Rogues by riding Storm’s Extreme Gear himself. With some trouble, Sonic quickly grasps the control of the Extreme Gear, and goes after their leader, Jet the Hawk. After exchanging some blows, Sonic passes by Jet, but is then quickly blown off the Gear by Jet, and the Babylon Rogues escape. Sonic however, is thrilled to have found someone who can give him a challenge.

The next day, Sonic, Tails and Knuckles sees Dr. Eggman on the monitors announcing the EX World Grand Prix and that the price is the Chaos Emeralds, which serves as an entry feet. Sonic is initially suspicious about Eggman’s motives, but when he sees that the participants Dr. Eggman had rounded up are the Babylon Rogues, Sonic decides to enter.

After the qualifications rounds, Sonic is not worried about Eggman plans, but then runs into Amy who had also signed up for the tournament, much to Sonic’s disappointment. Sonic then listens to Tails explaining the legends of the Babylon Rogues, how they lost their home island, Babylon Garden and its treasure, until Wave the Swallow comes by and mocks the Extreme Gear Tails had created (and places a bomb on it), and Sonic is disgusted by it.

After some races, Sonic practices his Extreme Gear techniques, but is interrupted by Jet who mocks his attempts at mastering Extreme Gear before leaving. While Sonic is angered by this, he sees that Jet is a good Extreme Gear rider and that it is not a good idea to underestimate him. Tails then doubts the Extreme Gear he had made, but Sonic faithfully tells him not to worry.

At the final race, Sonic heads to the podium with Jet and their Chaos Emeralds. After receiving some final taunts from Jet, Sonic promises him that he would not lose and heads out to the race. After a difficult race, Sonic is about to win, but Wave detonates the bomb under Sonic’s Extreme Gear and causes him to lose. Jet then heads up to Sonic and tells him that the dirt suits him, which leaves Sonic outraged.

Sonic is then left witnessing Jet using the seven Chaos Emeralds in tandem with the Key to Babylon to reveal Babylon Garden itself, with the intension to claim its great treasure. Eggman however, steals the key so he can take the treasure for himself, believing it to be technology that he can use to conquer the world and Sonic and the gang heads out to stop him. When they arrive at Babylon Garden, Sonic is given a a new Extreme Gear by Tails and heads out catch Eggman, but is locked in a race with Jet who is after Eggman too. Seeing this as a rematch, Sonic tells Jet that he will show him what true speed really is.

Sonic eventually beats Jet and corners Eggman, but stops when Eggman reveals that he is holding Amy hostage. Sonic, however, pulls out the same move on Jet used on him earlier and blows Eggman (and Amy) away, before handing the key to Jet, who sees this as an act of pity. As the Rogues heads in to claim the treasure, Sonic decides it is time to leave, but then has to face Amy, who is angry at him for endangering her with the moved he used on Eggman. After the Rogues heads into Babylon Garden however, Sonic hears a roar and decides to check it out. As he and the other arrive inside the Babylon Garden, Sonic sees the Babylon Guardian and is forced to fight it.

After beating the Babylon Guardian, Sonic and jet finds the Treasure of Babylon, which is revealed to be a Magic Carpet, much to the disappointment of Eggman, who had just arrived to steal it. With the whole ordeal over and with their rivalry more friendly, Sonic asks Jet if the Rogues are leaving, to which Jet agrees on, since there more treasure out there to find, and Sonic promises that he will be ready to race Jet next time they meet.

Defying Gravity
In the sequel Sonic Riders: Zero Gravity (2008), Sonic is driving with Tails and Knuckles through Monopole, and is fumbling with an mysterious meteorite Tails had found. On their way to Megalo Station, Sonic and the others are attacked by SCR-HD and a group of SCR-GP, a part of a current global robot rampage who is after the meteorite. In the insuring chase, the group crashes and Sonic nearly falls to his death, but saved by the meteorite, which Sonic discovers can manipulate gravity.

As they hide for the robots, Sonic is taken by surprise as Amy sneaks up in him. Sonic questions Amy what she is doing here and learns that she is being chased by the robots too, because she has a meteorite similar to Sonic’s. Sonic then decides to head to creator of the robots, MeteoTech, to get some answers. Once at MeteoTech, Sonic and the gang are discovered by security. However, the Babylon Rogues arrives, much to Sonic’s surprise, and Jet repels the SCR-GP’s with another meteorite. Jet reveals he is after the meteorites, called the Ark of the Cosmos and wants to challenge Sonic. Sonic is initially eager to face Jet’s challenge, but decides to postpone it as the alarm sounds and more robots show up.

As Sonic races Jet to the control room, Sonic is surprised to find Eggman, who is the owner of MeteoTech. Sonic immediately suspects that Eggman is behind the robot rampage, but he claims that he has no part in it. However once Eggman recognizes the Ark of the Cosmos on Sonic’s wrist, Sonic sees that he is holding back something and demands that he reveals everything. Eggman tells that MeteoTech’s computer is powered by one of the Arks of the Cosmos and that the robot leader, SCR-HD, which also happens to have an Ark of the Cosmos, seeks them for reasons unknown. The group then notices that Amy is being chased by SCR-HD, and Sonic heads out to save her, leaving the Rogues behind.

Once arriving there, Sonic finds Amy unharmed, and learns that SCR-HD had suddenly blown up and that Storm had taken its Ark of the Cosmos. Tails deduces that to stop the robots, they must remove the Ark in MeteoTech’s computer. Following a lead Storm had muttered, Sonic and the rest heads to the Gigan Rocks, a place no one has returned from alive, leaving Sonic thrilled to check out.

Once there, the group learns from the ruins that the Arks of the Cosmos are power units for an ancient spaceship, which Sonic figures out is Babylon Garden. Sonic then sees Jet chasing Eggman and learns from that and the ruins, the location of Eggman’s Ark of the Cosmos and MeteoTech’s computer. There, they find the Crimson Tower, and the Babylon Rogues, who reveals that Eggman stole their Arks of the Cosmos. Tails concludes that Eggman plans to use them to control all the world’s robots, and Sonic sees that this is his newest plan to conquer the world. Sonic is about to head out, but Jet intercept him and demands the race Sonic has postponed and Sonic gladly agrees. Jet then bets that however reach Eggman first get all the Arks of the Cosmos and the title of the fastest in the universe and Sonic agrees on the terms, thinking it sounds like fun.

The race eventually comes to a draw, as both Sonic and Jet stops Eggman at the same time. Sonic then gives his Ark of the Cosmos to Jet as he no longer needs it and takes his leave. Jet however, accuses Sonic for running away, since their race did not have a winner, but Sonic tells him that they will settle the score at the next World Grand Prix. Suddenly however, SCR-HD appears and takes all the Arks of the Cosmos to Babylon Garden. This results in Babylon Garden transforming into Astral Babylon and forms a black hole that threatens to consume the planet. Sonic then goes ahead with Tails, Knuckles and the Babylon Rogues behind him, to Astral Babylon to disconnect the engine. There they find SCR-HD, which had transformed into Master Core: ABIS and merged with the black hole. However, by using its own power against it, Sonic and the others stops Master Core: ABIS and saves the world.

Sonic later returns to the city and learns from Tails that the Ark of the Cosmos had a program which caused the robots to go amok and to collect them when they were hit by their influenced. Sonic then hears Jet calling out his name and come flying by, and Sonic sees that he challenges him to a new race. Sonic enthusiastically accepts this and races Jet throughout the city.

Racing Rivals in Rematches
In Sonic Free Riders (2010), Sonic and the rest of Team Sonic enter the newest World Grand Prix, which is once again hosted by Dr. Eggman (under the poor alias as King Doc) as Team Heroes. Sonic and the team however, simply participates for the sake of the competition, rather than the large cash price. When they introduce themselves to the viewers of the races, Sonic express his excitement and readiness to compete in the tournament, but Tails thinks that the races seems fishy, and Sonic expects that Eggman is planning something.

In their first race, Team Heroes sees that their first opponents are Team Rose and Sonic is openly disappointed and confident that they can beat them. As their team wins one challenge after another, Sonic is berated by Amy for not taking it easy on her, but Sonic insists on taking this competition seriously. Eventually, Team Heroes claim victory over Team Rose, but Sonic is left to face Amy who demands a date with him to make it up for him beating her, and he questions her why he owes her a date for winning.

For their next race, Sonic and Team Heroes goes up against Team Dark. During the race, Knuckles suspects Team Dark’s member, E-10000B for foul play, but Sonic thinks he is just imaging it.

In the end, Sonic and the team defeats Team Dark and advances to the finals. There they meet the Babylon Rogues, and Sonic says that he is not surprised that Jet and his team had made it to the finals. At first Team Heroes seemly beats Team Babylon, but when Sonic learns that they had mechanical troubles, Sonic calls for a rematch. Jet questions Sonic why he would risk their victory in a rematch, but Sonic open-heartedly assures him that they deserve a rematch. Jet then accepts it, but warns Sonic that he would regret it, but Sonic is as confident as ever, and the two of them engages in a heated on-on-one rival race, where Sonic emerges victorious.

After the race, Sonic learns from Omochao that Team Babylon is about to leave, but before they could, Sonic thanks Jet for the race and looks forward to their future rematch.

As the tournament progress, Sonic and Team Heroes receives their own fair share of losses, but despite this, Sonic continuously displays good sportsmanship and enjoys participating. At the end of the tournament, all teams come down with an equal amount of victories and losses, and Sonic and the other teams heads out to collect the price, but Eggman (as King Doc) declares that they have one, final race against his Gear-Jockeys. Sonic tells Eggman to drop the act, but Eggman makes them race anyway and Sonic senses something is up.

After the first round, Eggman decides to drop his disguise and reveals that he hosted the World Grand Prix so that he could collect the rider’s racing data with his E-10000 robots in order to create the ultimate Extreme Gear which he can use for his own agenda, but Sonic thinks that his plan is just lame.

Eggman then challenges Sonic and the others to a race, but loses. Sonic then notices that E-10000B is acting funny and sees Metal Sonic emerging from it, and learns that Metal Sonic had stolen Eggman’s data and giving him fake data, so that he could take it for his own. Sonic then notice that Metal Sonic is challenges him to a one-on-one race and despite being told that Metal Sonic cannot be beaten on a Extreme Gear, Sonic gladly accepts the challenge, thus giving Metal Sonic the rematch he had promised him long ago.

Despite possessing the data of the best Extreme Gear riders in the world, Sonic defeats Metal Sonic, and Metal Sonic runs away. As Eggman curses Metal Sonic for ruining his plan, Sonic taunts Eggman for letting him ruin his own plan and that it makes his job as a hero easier. The other teams then leaves as the price was a lie, but Sonic tells them that they had a great time at the World Grand Prix nonetheless.

Two Worlds Collide
Sonic appears in Sonic Rush (2005), the first Sonic game for the Nintendo DS. This time, Sonic has to face both Dr. Eggman and the new foe, Dr. Eggman Nega, as Sonic's world is brought into flux with another, because the Chaos Emeralds' counterparts in that world, the Sol Emeralds, had been stolen by Dr. Eggman, with the help from Nega.

The story starts with Sonic coming across Dr. Eggman who claims that he would soon possess “the ultimate power”, but Sonic assures him confidently that he will stop him. After defeating Eggman, Sonic sees that he dropped a Sol Emerald, but then suddenly he meets Blaze the Cat, the guardian of the Sol Emeralds, who appears in a burst of flames, takes the emerald and leaves. Sonic later explains about what he had just witnessed to Tails and the duo heads out to stop Eggman.

At the Water Palace, Sonic runs into who he believes is Dr. Eggman, but the villain reveals himself to be Eggman Nega. After defeating him, Sonic and Tails heads to Tails’ Workshop, where they learn that there is a rift in the space-time continuum that threatens reality itself. While Tails thinks that Eggman Nega has something to do with, Sonic thinks that Blaze might also be a part of this. As they search for information and fight Nega, Sonic hears from Vanilla that Cream is together with Blaze and she tells where to find them. Sonic then runs off to find Blaze and get some answers.

After a lengthy search, Sonic and Tails finds Blaze and Cream, and Sonic asks Blaze if she knows anything about Eggman Nega. Blaze however, despite having been told by many to seek Sonic’s help, tells him that she will deal with this crisis and Eggman Nega alone. Sonic, on the other hand, tells Blaze that things do not work that way, but she firmly insists and leaves, but Sonic follows her. Sonic eventually tracks Blaze to the Dead Line where they face both Eggmans. While Sonic insists on participating, Blaze angrily refuses his help and tries to force Sonic to leave by fighting him. While battling, Sonic tries to make Blaze stop and says that she should not carry everything on her own shoulders, but to no avail. As their fight comes to a draw, Sonic sees that Blaze is still willing to protect the Sol Emeralds even when completely exhausted and understands that she must have had a rough past. He then tells her not to handle too much on her own and be true to herself, and Blaze comes to understand that she can rely on others. With their differences set aside, they finally introduce themselves and become friends.

With Blaze on their side, Sonic learns that space-time rift is due to the merging of her world and Sonic’s and Eggman Nega is to blame. Sonic then heads out to confront Nega on behalf of Blaze to stop this, since she is not in shape to fight after their confrontation, and defeats Nega. In the aftermath of the fight, Sonic is welcomed back by his friends, but runs off when he sees Amy coming.

After collecting all seven Chaos Emeralds, Sonic comes to Blaze’s aid as she is defeated by Dr. Eggman and Eggman Nega in the Egg Salamander and had all seven Sol Emeralds drained of their power, but the doctors leave as he arrives to prepare for their coming fight. As Blaze despairs for failing her duty, Sonic tells her that everything would be fine, and with him and with his friends backing Blaze up, he assures her that with the friendships she have come to understand and embrace, the Sol Emeralds would never lose their power and the Sol Emeralds recharges. Sonic and Blaze then use both sets of emeralds to become Super Sonic and Burning Blaze and together they defeat the Eggmans.

As the space-time continuum begins to restore itself, Sonic and Blaze says their final goodbyes as they prepare to return to their respective worlds, but Sonic promises that they will meet again which Blaze hopes for. The two of them then sake hands as a sign of friendship and respect as the space-time continuum pulls them apart and returns them to their own worlds. When Sonic returns home, he finds Cream, who is sad over Blaze’s departure, but cheers her up by telling her that Blaze would be back.

Setting Sails In New Worlds
Sonic Rush also had a sequel called Sonic Rush Adventure (2007). The story begins as Sonic and Tails are out investigating an unknown energy reaction in a storm, but they get sucked into a hurricane. Having crashed, Sonic and Tails washes ashore on Southern Island where they meet Marine the Raccoon, a rash girl who dreams of adventure. As they find themselves on an unknown island, Sonic and Tails decides to explore the surroundings. The next day, Sonic and Tails find Marine working on her own boat, but she ends up destroying it. The duo then helps Marine constructing a new boat and the trio begins exploring the surrounding islands.

On their journey across the islands, the group is attacked by several robotic enemies. Sonic also encounters Johnny, who becomes his rival in water bike racing. When arriving at Coral Cave, Sonic meets Captain Whisker and his pirate crew, who is the ones behind the attacks. Suddenly, Sonic sees someone who attacks the pirates and is surprised to see that it is Blaze the Cat. Despite this surprise meeting, Sonic gladly teams up with Blaze to fight off Whiskers’ henchmen.

After the fight, the pirates escape with the Jeweled Scepter, a powerful treasure from Blaze’s homeland which was hidden in Coral Cave and which Blaze tried to protect. Sonic questions Blaze why she is here and not in her own world, but realizes that they must have been transported to Blaze’s world during the storm. After explaining their story to Blaze, the group sees this meeting as a sign that both their worlds might be endangered by the pirates, now that they have the Jeweled Scepter, and Sonic suggests to Blaze that they should work together to get the scepter back, which she accepts.

The four of them then travels the sea in their search for the pirates. Eventually, they manage to locate the pirates’ hideout in some ancient ruins. Before heading in there however, the group decide to leave Marine behind as she may endanger the mission, but she objects. While Sonic tries to be gentle about the reason, Blaze bluntly says that she is a nuisance, and Sonic and Tails silently agrees with her, which leads to Marine running off. While Tails feels it was a harsh comment, Sonic assures him that she will get over it.

At the pirates’ hideout, Sonic faces Whisker and his right-hand man, who is revealed to be Johnny, alongside Blaze. Despite beating them however, Whisker escapes and Sonic then sees that Marine is going after the pirates to prove herself, but ends up being caught by the Ghost Titan. Fortunately, Sonic comes up with a plan to distract Whisker by letting Tails pretend the scepter is somewhere else on the ship and he and Blaze save Marine. Sonic and Blaze then destroy the Ghost Titan together and escapes, while the pirates goes down with the collapsing ship. With Marine having reclaimed the Jeweled Scepter, the group head back to Southern Island.

After collecting all seven Chaos Emeralds and Sol Emeralds, Sonic and Tails plans to return home, but they learn that the Jeweled Scepter had been stolen again. An earthquake then occurs and in the wake, the thieves reveal themselves to be Dr. Eggman and Eggman Nega in the Egg Wizard, and Sonic learns that they were the ones who created the pirates, so that they could use the Jeweled Scepters incredible power to build Eggmanland upon both worlds. Sonic and the gang head out to confront the Eggmans but are too late as the villains tap into the Power of the Stars with the scepter. As Nega taunts Blaze by treating to destroy her kingdom, Sonic keeps Blaze calm for hers and her people’s sake. They then use the Chaos Emeralds and Sol Emeralds to become Super Sonic and Burning Blaze and they fight the Egg Wizzard. As they are about to win however, Eggman Nega tries to destroy them, along with the world, but Marine distracts them, and with Blaze’s aid, Sonic deals the final blow and destroys the Egg Wizard.

The next morning, Tails constructs a vessel for him and Sonic to return home in. As Sonic prepares to leave, Blaze suggests to him that the Sol Emeralds and the Chaos Emerald is responsible for bringing them together again. Sonic is initially confused by her statement, but then says positively that they can never know for sure. As they are about to leave, Sonic says goodbye to Blaze and they shake hands once more, signifying their growing friendship and respect. As they are about to take off however, Sonic and Tails sees Marine comming in her new boat to say goodbye. While she is sad that they have to leave, Sonic and Tails promise her that they will meet again someday. With these final goodbyes Sonic and Tails head back to their own world.

Transcending Time and Space
Sonic the Hedgehog, which celebrated the 15th anniversary of the series, was released in 2006 and featured the first appearance of Blaze the Cat on a home console game and a new character called Silver the Hedgehog who possesses powerful psychic abilities.

In this game, Sonic visits Soleanna, the City of Water. Here, Sonic arrives to save their monarch, Princess Elise, from Dr. Eggman who had come after the Flames of Disaster known as Iblis to help him control time and rule the world, which was sealed inside Elise. During their adventures, the two of them would come to develop a strong relationship.

While escaping Eggman, Elise asks Sonic why he helped her, but he just says "no special reason". By distracting Sonic with some robots, however, Eggman kidnaps Elise and escapes, but not before Elise gives her Chaos Emerald to Sonic, who promises that he will save her. The next day, Tails joins Sonic in his mission to save Elise and they chase after Eggman’s ship, the Egg Carrier, but fail to catch it.

After returning to the city, Sonic and Tails learns that Eggman had been seen in Dusty Desert. They travel there and find Elise, who is happy to see Sonic, but Eggman appears and tries to stop them. Sonic and Elise manages to escape anyway by having Tails create a division. Sonic and Elise soon arrives at the plains and Elise thanks Sonic for his help. She sees that Sonic is hurt, but tells her that he is fine. While treating him, Elise apologizes for Sonic’s injury, but Sonic merely tells her to smile, which is all the reward he needs. Elise then fills Sonic in on the Flames of Disaster’s history and Solaris (the sun god honored by Soleanna), and worries what could happen if Eggman unleashed Solaris’ wrath. Suddenly, Sonic grabs Elise's hand and they runs through the plains. After cheering her up from their run, Sonic gives Elise some useful advice to go by.

After Sonic and Elise return to the city, Sonic is attacked by Silver the Hedgehog, who calls Sonic the "Iblis Trigger" and claims that Sonic’s actions will destroy Silver's future. Sonic initially has the upper hand in their fight, but Silver catches him off-guard and psychokinetically throws him into a building, incapacitating him. While Sonic is distracted, Eggman kidnaps Elise again and Sonic tries to run after him, but Silver stops him. Luckily, Amy appears and stops Silver and after thanking Amy, Sonic runs after Eggman.

Sonic soon after meets up with Tails and Knuckles whom gives him a message from Eggman, who demands Sonic’s Chaos Emerald in exchange for Elise. While Tails and Knuckles are positive it is a trap, Sonic decides to go anyway, intending to thank Eggman for telling him of Elise’s whereabouts. After arriving at Eggman's base, Sonic gives Eggman the Chaos Emerald, but Eggman tricks them and sends them to the future. There Team Sonic meets Shadow and Rouge who had been sent there by Mephiles (Solaris’ mind and conscience). After learning from Rouge and Shadow where they are, they plan to return to their own time by using Chaos Control with the Chaos Emeralds.

While searching for Chaos Emeralds, Sonic, Knuckles and Tails sees Silver and Blaze talking with Mephiles, who tells them that Sonic is responsible for the devastation of this future and takes them back in time to kill Sonic. Sonic and the gang then meet up with Rouge and Shadow after learning the location of a Chaos Emerald and retrieve it from an enraged Iblis. With two Chaos Emeralds in their possession, Sonic and Shadow performs Chaos Control, thus creating a rift in time, and Sonic, Tails and Knuckles return to the present.

Sonic then runs off and saves Elise from Eggman's train, but he is attacked by Silver again, thus allowing Eggman to kidnap Elise once more. Fortunally, Shadow arrives and fights Silver, while Sonic runs off and rescues Elise from a lethal fall. As they escape Eggman’s forces, Sonic takes Elise to a beautiful location with Cherry Blossom trees and a lake to cheer her up. There, Sonic tells Elise that he will leave once he defeats Eggman. Elise thanks Sonic for this adventure and makes him promise to remember that place. While Elise nearly cries because Sonic has to leave, Sonic comforts her and tells her to keep smiling.

Sonic returns her to the castle afterwards, but unfortunally, Eggman kidnaps Elise again after he threatens to destroy Soleanna, and Sonic runs off to save her. On his way, Sonic encounters Silver once more, but this time Silver is willing to help Sonic save Elise, which he accepts. Unfortunally, Eggman’s ship crashes and explodes with Elise inside. As Sonic despairs at the loss of Elise, Silver comes up with the plan to send Sonic back in time to save Elise. Using Chaos Control and two Chaos Emeralds, Sonic and Silver creates a time rift, but before leaving, Sonic tells Silver that he will change Silver future too by saving Elise, and thanks Silver for his help. Sonic arrives the day before the crash, and borders the Egg Carrier as it launches. He then defeats Eggman a final time and escapes the exploding Egg Carrier with Elise.

As Sonic and Elise return to the city, Mephiles distracts them with his Chaos Emerald and impales Sonic through the back with an energy beam, killing him instantly. As Elise realizes that Sonic is dead, she breaks into tears, thus releasing Iblis from within her. Mephiles then merges with Iblis and Solaris is reborn. Solaris then proceeds to create a time rift for him to consume time itself. There, the games main cast sees Sonic’s dead body in Elise’s arms, each showing sadness at his dead. As they learn about Solaris’ intention, Silver comes up with a plan to destroy Solaris, but Shadow states that with Sonic gone, they stand no chance of defeating Solaris.

Sonic’s soul at this point however, had yet to pass on, and Elise senses his presence. Realizing that it is not too late, Tails, Omega, Knuckles, Silver, Rouge, Amy, and Shadow gather all the Chaos Emeralds to restore Sonic to life, and with Elise's kiss, Sonic is revived as Super Sonic and he thanks her for bringing him back. He proceeds to turn Shadow and Silver into Super Shadow and Super Silver and they battle Solaris. After they defeat him, Sonic and Elise are sent back in time to where Solaris was just a flame in a candle. If Elise blows out the candle it will destroy Solaris forever, but with Solaris gone, the events of the adventure will be negated and Elise will never meet Sonic. Elise initially chooses Sonic over the world, but Sonic tells Elise to smile and she extinguishes the candle. Time is reverted, but Sonic still travels to Soleanna and the wind created from his speed causes Elise's memory to trigger, but she eventually ignores it. As the festival proceeds, Sonic watches happily as one of Elise's feathers floats skyward, hinting that both Sonic and Elise remembered.

Hunting for Cards
Sonic Rivals was the first Sonic game for the PSP (Playstation Portable). Sonic, Knuckles, Shadow, and Silver battle each other as they go after Doctor Eggman (actually Eggman Nega in disguise).

In Sonic Rivals, the mysterious Onyx Island had appeared out of nowhere and Sonic decides to check this island out with Tails. When they arrive however, Tails disappears and Sonic tries to find him. As he searches the island, Sonic finds who he believes to be Dr. Eggman, but is Eggman Nega disguised as Dr. Eggman (Sonic however, does not realize this throughout the game) and asks what he has done, and Eggman Nega reveals that he had turned not only Tails, but also Amy, into cards with a special camera. Suddenly Knuckles appears and wants to face Eggman Nega, who he believes had stolen the Master Emerald. Eggman Nega then tells them that to get the cards back, they have to catch him, and Sonic races Knuckles to see who gets to face Eggman Nega first.

After the race, the two find Eggman Nega and they team up to fend off one of his creations, but Eggman Nega escapes. As Sonic gives chase to him however, he runs into Silver for the first time (since the events of Sonic the Hedgehog (2006) were negated), who has come to bring Eggman Nega back to the future. As Silver insists on getting to Eggman Nega first, Sonic gladly accepts the challenge, and the two of them race after Eggman Nega. As Sonic reaches Eggman Nega, he demands the cards back, but Silver still insist on going first. Sonic starts to get annoyed by Silver’s attitude and it breaks down to a fight between them.

As Sonic gain the upper hand in their fight, Silver teleports him to another location. Surprised, Sonic starts to look around and finds Shadow. He sees that Shadow is after Eggman Nega as well and Sonic challenges him to a race to see who gets to Eggman Nega first. Sonic eventually outraces Shadow, much to his own pride, and finds Eggman Nega, and demands to know what he is up to. Eggman Nega however, retaliates by unleashing Metal Sonic on Sonic, who is surprised to see his old rival again. After Sonic defeats Metal Sonic, he thinks about Eggman Nega’s plan, but then runs into Silver again, who is surprised to see him so soon. Sonic then tells Silver that he will share his information with Silver, if he beats him in a race to Eggman Nega, and the pair gives chase to him again.

Sonic and Silver eventually corners Eggman Nega and Sonic demands Tails’ card back, but Eggman Nega still intends to defeat Sonic. Sonic however, tells him that he would never win, and he and Silver begin fighting Eggman Nega’s newest robot. Eventually they defeat it and Sonic reclaims Tails’ card, while Eggman Nega escapes. Sonic then frees Tails and assures him that he will stop Eggman Nega, but then Knuckles reappears and Sonic is challenge by him to race to see who gets to Eggman Nega first.

Sonic eventually reaches Eggman Nega first and face both him and an upgraded Metal Sonic, but still wins. Frustrated at his constant defeats, Eggman Nega tell Sonic that he now plans to turn the world into a card that he can control as he wishes and escapes, much to Sonic’s frustration. Tails however, appears in the Tornado and Sonic is taken to Eggman Nega’s base. As Sonic ventures to and through Eggman Nega’s base, Knuckles, Shadow and Silver and team up with him to stop Eggman Nega as they put aside their differences, and Sonic accepts each of their help.

At the center of the base, Sonic and the others find a large spaceship with Eggman Nega’s special camera equipped on that he plan to use to turn the world into a card. Sonic then sees that Eggman Nega plans to fuel the device with Amy’s card (which Sonic had forgot about) and some other cards he had taken, but the four rivals head into battle and destroys the spaceship as it takes off, thus foiling Eggman Nega’s plan for good.

After the battle, Sonic saves and frees Amy, who believes this means Sonic wants to marry her. Sonic on the other hand, comes up with an excuse by telling her that he has to find the remaining captives in Eggman Nega’s cards and immediately runs off.

Save the Chao and Race with Rivals
Sonic Rivals also had a sequel called Sonic Rivals 2. While on his own, Sonic receives a call from Tails, telling him to meet up him on an island. Once arriving there, Sonic hears from Tails that a bunch of Chao has gone missing. After hearing from him that Eggman has something to do with this, Sonic teams up with Tails to find Eggman and get some answers. As they about head out however, Sonic sees Knuckles with Rouge and teases him by asking if they are on a date. While annoyed, Knuckles says he has to find Eggman first, and Sonic asks why. Knuckles reluctantly answers that the Master Emerald had been stolen, but Sonic is not surprised. Sonic however insist on finding Dr. Eggman first, and the two face off in a race to find him.

The two eventually find Dr. Eggman, who really is Eggman Nega masquerading as Dr. Eggman once more (and again, Sonic does not realize this throughout the game). Sonic demands to know what he has done with the missing Chao, but Eggman Nega claims he has nothing to do with it. Sonic however does not buy it, and Eggman Nega attack Sonic and Knuckles in his newest robot. After the fight, Sonic and Tails follows the escaping Egman Nega through a forest, and they find a page dropped from Eggman Nega which describes a creature called the Ifrit, which Sonic and Tails begin to think has something to do with the Chao. Soon after, Sonic runs into Silver the Hedgehog and Espio the Chameleon and guesses that they are after Eggman Nega too. Seeing that Silver is determined as ever not let Sonic get in his way, Sonic challenges Silver to a number of fights to see who gets to face Eggman Nega first.

The group eventually finds Eggman Nega, and Sonic questions him why he is running away if he is not involved with the missing Chao, but Eggman Nega defiantly attacks them in a new robot. After the fight, Sonic and Tails follows Eggman Nega to a city, but suddenly, Sonic sees Shadow with Metal Sonic. Suspicious at why Metal Sonic is involved, Sonic and Tails decides to follow the pair, with Sonic following Shadow. After catching up with Shadow, Sonic begins questioning Shadow, but he refuses to give an answer, and they begin to fight. Suddenly however, Eggman Nega attacks them, but the two hedgehogs manage to fend him off.

Sonic and Tails then follows Eggman Nega to a wasteland, where they meet Knuckles and Rouge again. They reveal they are searching for the Master Emerald, but they need rings to fuel their Emerald Detector, and Sonic volunteers to search for rings. After Sonic had gathered enough rings however, Espio appears and takes his rings, as he and Silver need them to find Eggman Nega, but Sonic pursuits him. On the way, Sonic runs into Eggman Nega again, and demands to know his plan, and he says that if Sonic can beat his Egg Bull, he would tell him. Despite the untimely interference of Silver and Espio, Sonic and Tails manages to win. Sonic tells Eggman Nega to keep his promise and he reveals his plan to release the Ifrit into the world from a portal within a haunted mansion and Sonic and Tails head there to stop the Ifrit.

Once arriving at the mansion, Sonic and split up. While searching, Sonic runs into a shape shifting ghost and engages it victoriously in battle. Once reunited with Tails, they find Eggman Nega with their ghost counterparts, but Sonic sees that he is acting weird, and contributes it to ghostly possession. After fighting Eggman Nega, Tails finds the missing Chao, which Eggman Nega had planned to feed to the Ifrit to make it invincible, and Sonic tells Tails to bring the Chao to safety while he searches for Eggman Nega.

Sonic and Tails eventually finds the portal to the Ifrit's dimension, which is about to close (due to Shadow’s and Metal Sonic’s actions) and they head in to find Eggman Nega before it is too late. As Sonic and Tails ventures through the Ifrit’s dimension, they face the Ifrit itself, who takes control of Tails. Seeing no choice, Sonic faces both Tails and the Ifrit to stop it from destroying the world. Despite Sonic occasionally falling prey to the creatures mind control himself, the two friends manage to prevent the Ifrit from leaving its world, and escapes before the portal closes. With the Ifrit stopped, the world safe and the Chao rescued, Sonic sees no reason to find Eggman Nega, and he and Tails head to the Chao Garden to get some rest.

The Legendary Blue Hedgehog
In 2007, Sonic and the Secret Rings was released. After waking up from his nap, Sonic encounters the genie of the ring, Shahra from the world of the Arabian Nights. She reveals that an evil genie called Erazor Djinn is absorbing her world, the very power of the book itself and if he is not stopped, he would enter Sonic's world too. She also reveals that Sonic is the "Legendary Blue Hedgehog" foretold in legend, who can stop him. More than willing to help, Sonic agrees to help Shahra and she leads him into her world. While entering the Arabian Nights, Sonic encounters Erazor, who demands that Shahra gathers the seven World Rings, but she refuses. Trying to punish her with a curse, Sonic takes the blow for Shahra and is shot in the chest with a flaming arrow. Erazor then demands, before he leaves, that Sonic gathers all the World Rings before the arrow burns out, or he will die. Sonic then heads into the Arabian Nights, with Shahra at his side, intending to stop Erazor before it is too late.

On his adventures through the Arabian Nights, while stopping Erazor's plans along the way, Sonic collects all the World Rings and learns about a past relationship between Shahra and the Erazor Djinn. With the help of King Solomon, Sonic eventually faces the Erazor Djinn in his stronghold and defeats him, who then retreats under a sealed door in there. Using the Seven World Rings, Sonic opens it and finds Erazor waiting for him. Sonic then tells Erazor to remove the curse, but he does not keep his word. Instead, Erazor takes the World Rings by manipulating Shahra and tries to sacrifices Sonic to gain control of the rings, but Shahra saves Sonic at the cost of her own life. Erazor then uses the seven World Rings, hoping to gain total control over the Arabian Nights, but ends up transforming into the incomplete Alf-Layla-wa-Layla. Three of the World Rings is then absorbed by Sonic who transforms into Darkspine Sonic, which break the curse, and he defeats Alf-Layla-wa-Layla.

With Erazor defeated, Sonic decides to use Erazor's lamp, given to him by Shahra earlier, to make him grant three wishes: Revive Shahra, restore the Arabian Nights and seal Erazor himself away in his lamp forever. Having no choice, Erazor grants all of Sonic's wishes and the Arabian Nights are saved. Though Shahra cries over the faith of Erazor, Sonic wishes forth a mountain of handkerchiefs, allowing her to cry as much as she needs to.

Becoming A Knight
The sequel, Sonic & the Black Knight, came out in 2009. This time, Sonic was suddenly called into battle in the world of King Arthur by Merlina the Wizard, in order to defeat King Arthur, who had become the evil and tyrannical Black Knight through the power of the Scabbard of Excalibur, which made him immortal. After a brief retreat from King Arthur, Merlina leads Sonic to the Sacred Sword Caliburn, a sentient sword who would become Sonic's teacher in knighthood, hoping to give Sonic a better fighting chance.

After another brief confrontation with King Arthur (who left because he did not think Sonic was a threat), Sonic and Caliburn sought out Nimue, Lady of the Lake who knew how to stop the Scabbard of Excalibur. However, she would only give out the secret about the Scabbard to Sonic, if he passed a test of true knighthood, which he eventually did. He learned from her that he had to collect all of the Sacred Swords and that their united power would negate the Scabbard's power. Having already gathered two of them from his fights with the Knights of the Round Table along the way, Sonic went to get the last one from Percival and succeeded.

With all four Sacred Swords, Sonic faced King Arthur and defeats him. As Sonic gives the Scabbard of Excalibur to Merlina, she reveals that she had used Sonic all along so that she could use the scabbard for herself to prevent the grim fate that awaited the world of King Arthur, though at the cost of many lives.

Sonic eventually went and faced Merlina himself, with the help from Knights of the Round Table, but recieved a massive beating from Merlina, and got Caliburn cut in half. Nevertheless, Sonic refused to give up, which brought forth the power of all the Sacred Swords, transforming himself into Excalibur-Sonic and Caliburn into Excalibur. They defeated Merlina and Sonic convinced Merlina to let go of her driving sadness and live her life to the fullest, despite her world's fate. As the Knights of the Round Table thinks about disbanding now that they do not have a king, Caliburn reveals to them that he chooses the king, which meant that Sonic was the true King Arthur of this world, much to Sonic's surprise. Depite this new title, Sonic returns home, only to face Amy who claims that his story was just an excuse for forgetting their date.

Rise of the Brotherhood
In Sonic Chronicles: The Dark Brotherhood Sonic assumes the leadership of a group of heroes in their fight against a group of evil echidnas called the Nocturnus Clan. In the game, Sonic has low damage power and armor, but he will almost always attack first in a round and he gets three attack per round due to his speed.

The story starts with Sonic, Tails, Knuckles and Amy facing Dr. Eggman onboard the Egg Carrier and succeeds in making the ship crash into Metropolis and Eggman was presumed dead.

With Eggman and his forces gone and no need for him to be a hero anymore, Sonic goes on a long vacation, spending his time exploring the world. One day however, Sonic receives a call from Tails who says that the Chaos Emeralds had been stolen and that Knuckles had been kidnapped by a group dubbed the Marauders. Tails tells him that they need his help to save Knuckles and Sonic gladly agrees to help. As the adventure progresses, Sonic manage to gather many of his friends and allies in the fight against the Marauders.

Eventually, Sonic and his friends manage to save Knuckles from the Marauders, but then discover Angel Island had been hijacked. Sonic suspects that Eggman is behind this, due to the Marauders using Eggman’s robots, and the group manages to locate him in Green Hill. Upon finding him however, Eggman claims that he is against the Marauders as well. Eggman then claims to have reformed and is willing to join Sonic in his fight against the Marauders as he can lead them into Metropolis where the real hijackers, the Marauders, had drawn Angel Island to with the Chaos Emeralds. While Sonic is clearly against it, he lets him join.

On the way there, Sonic and the others meet one of the soldiers from the Marauders, called Shade who reveals that the Marauders are a group of echidnas called the Nocturnus Clan, exiled to the Twilight Cage in ancient times, much to Knuckles surprise. Despite defeating her, Shade blocks their way to Metropolis, but Sonic and the others manages to find a way around it. In the meanwhile, Sonic tires to support Knuckles, who had found others of his kind, but is forced to fight them. Once in Metropolis, they divide into two teams with Sonic and Knuckles going to Angel Island to prevent the Nocturnus Clan from stealing the Master Emerald.

There the pair meets the Nocturnus Clan’s leader, Imperator Pir'Oth Ix, who states his plan to rule the world, which shocks his servant Shade, who just wants to leave the Twilight Cage. Despite their best efforts, Sonic and Knuckles are unable to stop Ix from stealing the Master Emerald, who uses it to create a wormhole into Sonic’s dimension so that they can conquer it, and Angel Island fall from the sky. With the Nocturnus Clan now possessing all the emeralds, everyone begins to despair, but Sonic refuses to give up and assures them that they will stop Ix. The team then comes up with the plan of going after Ix into the Twilight Cage and reclaim the emeralds, and Shade joins Sonic’s team to stop Ix’s plan.

After constructing the Cyclone, Sonic and the others enter the Twilight Cage, while Eggman stays behind to watch the entrance to the Twilight Cage. Once inside the Twilight Cage, Sonic and the other begin hunting down the Chaos Emeralds and the Master Emerald. In their search, Sonic and the team manages to gain the alliance of the alien races residing there, they learn of Emerl's origin and Sonic offers Shade to live his world once it is over, which she accepts. As the team prepares to invade Nocturne to find the last emeralds, Sonic manages to unite the conflicting alien races in the battle against Ix, and with their help, Sonic and the others infiltrate Nocturne. Once there, they split in two teams, with Sonic and Tails leading their group and Knuckles and Shade leading the other, to find the emeralds.

After Sonic and Knuckles reclaim the last Chaos Emeralds from the Gizoids, Charyb, and Scylla, Sonic and his group heads to Ix’s throne room to stop Ix. There Sonic sees Knuckles talking to Ix and believes he is going to betray them, but is proven wrong as Knuckles remains loyal to his duty and attacks Ix. After Knuckles’ fight, Sonic then steps in and stalls Ix, while Knuckles gets the Master Emerald back and succeeds.

After the fight, Sonic tells Ix it is over, but the echidna leader refuses defeat and uses Nocturne’s power to become Super Ix, but Sonic retaliates by using the seven Chaos Emeralds to become Super Sonic and defeats Ix for good. As a final act however, Ix starts to close the wormhole out of the Twilight Cage, but Sonic and the others manage to get through just in time. When they return home however, Sonic and the others see much time had passed, thus allowing Eggman to rebuild his forces, which they face upon exit from the Twilight Cage.

Enter the Werehog
In Sonic Unleashed, the story begins after an unknown series of adventures, as Sonic arrives at Dr. Eggman's massive fleet in space and begins blasting through his forces, before he is confronted by Eggman in a powerful mech.

Forcing Sonic on the defensive, Eggman captures him, but Sonic retaliates by turning into Super Sonic and he destroys Eggman's mech, and trashes his fleet as well, as he chases the escaping Eggman. As Super Sonic chases Eggman to a space station, Super Sonic is caught in Eggman's Chaos Energy Cannon where Super Sonic has the Chaos Emeralds painfully removed from him, returning him to normal. With the emeralds power, Eggman fires the cannon at the planet, breaking it apart and awakes the ancient creature called Dark Gaia, in order to harness its power. In the process, a part of Dark Gaia's energy infects Sonic and turns him into a monster version of himself. As he is released from the trap, Sonic is rejected from the station by Eggman and falls plummeting towards the planet with the powerless Chaos Emeralds.

Moments before impact, however, Sonic is saved by a green light which breaks his fall. After recovering, Sonic finds an unconscious imp-like creature nearby. After he awakens, they introduce themselves, but Sonic realizes that the creature suffers from amnesia, as he cannot remember anything. Believing that he caused his memory loss by falling on him, Sonic promises to help him recover his memories, much to his delight. Dawn then breaks and Sonic returns to normal, much to his suprise.

The duo arrives at Apotos and Sonic decides to name his new friend Chip after an ice cream he had taken a liking to. After a day's fruitless search for someone who knows Chip, night falls and Sonic turns into his werehog form again, and he realizes the nature of this transformation. They soon run into Tails who is attacked by Dark Gaia's minions, but Sonic saves him. As Tails recognizes Sonic, even in his new form, Sonic explains his story to Tails, who suggests that they should talk to his friend Professor Pickle in Spagonia, who might know something about this, but they arrive only to hear that Eggman had kidnapped the professor for his knowledge about Dark Gaia.

Sonic, Tails and Chip track the professor down to Mazuri and they save him from his prison in Eggman's base. They learn from the professor that Dark Gaia is the reason that the planet had broken apart, but it had yet to be fully reborn due to its unnatural awakening. Due to this, Professor Pickle tells Sonic that he can restore the planet and the Chaos Emeralds by placing the emeralds in the Gaia Temples across the world.

Sonic and Chip returns to Mazuri just in time to fight off Eggman and they locate a Gaia Temple. Inside the temple, Sonic witnesses Chip's ability to activate the temple, and after placing a Chaos Emerald there, the emerald and a continent is restored. Hearing of his progress from Tails, Sonic sees this as a good opportunity to see the world.

When returning to Spagonia at night, Sonic encounters Amy, but is shocked to see that Amy did not recognize him as a werehog and becomes depressed as he thinks that he is not same person anymore. He later finds Any caught in a group of people possesed by Dark Gaia, but with Chip's help, Sonic exorcise the people. After saving Amy however, Sonic leaves before she can see him, but he eventually faces Amy with his condition.

Sonic and Chip continue their adventure across the world, healing it one piece at a time. However, as Sonic restores the sixth continent, Chip regains his memories inside the sixth temple. Sonic learns that Chip's real name is Light Gaia and that he had been fighting Dark Gaia in a continuous cycle of destruction and restoration of the planet since the dawn of time. Sonic comes to the conclusion that Chip is the reason he remains the same person, even when in werehog form, but Chip reveals that it is Sonic's own will and strong heart that prevents him from succumbing to the darkness inside him. After thanking Sonic for showing him the world and his help, Chip tries to leave to stop Dark Gaia on his own, but Sonic stops him and says that he will help his friend despite these revelations, which Chip accepts.

Sonic and Chip then arrive in Eggmanland in order to find the last temple. As they place final emerald in the temple and the last continent moves back into place, Sonic (in his werehog form) and Chip is attacked by Eggman in his Egg Dragoon. After Sonic defeats Eggman at the planet's core, Dark Gaia appears and knocks Eggman into the distance, before engaging Sonic and Chip. Seeing that Sonic holds the missing fragment of its power, Dark Gaia painfully sucks its energy out of Sonic, thus curing him of his werehog condition. All weak from the energy drain, Sonic tells Chip to run, but Chip calls upon the Gaia Temples to form the Gaia Colossus and together with Sonic, they fight Dark Gaia.

During the fight however, Dark Gaia fully matures and becomes Perfect Dark Gaia and prepares to cast the world into darkness. Sonic, determined to stop it, harnesses the Chaos Emeralds full power and becomes Super Sonic. Together, the heroes slay the terrifying monster, but Super Sonic was given a tough fight and he falls unconscious in his normal form after defeating the beast. He is then returned to the surface by Chip, as he gets sealed inside the planet and returns to dormancy. After landing on the surface, Sonic finds himself where he met Chip and finds his necklace, which he keeps as a bracelet. As he hears Chip's final goodbye, Sonic pays his respect to his friend and runs off for new adventures, accompanied by Tails.

Episode 1
Sonic returns in an episodic downloadable title called Sonic the Hedgehog 4 as the sole playable character; this game takes place after the events of Sonic & Knuckles and takes place before the events of Sonic Adventure. Unlike its chronological predecessor, Sonic still retains his green eyes and Homing Attack in it.

In Episode I, Sonic had just finished his adventure in Sonic & Knuckles and had managed to finally destroy the Death Egg. With this whole ordeal over, Sonic decides to take a much deserved break from his adventures. He then parts with Tails and Knuckles for the time being, and Sonic ventures out on his own to explore new parts of the world. Sonic's break is cut short however, as Dr. Eggman reveals himself to be alive after their last encounter, and has returned to defeat Sonic for good with a new army of Badniks.

Sonic then chases and fights Dr. Eggman while collecting Chaos Emeralds through the four main zones Splash Hill Zone, Lost Labyrinth Zone, Casino Street Zone, and Mad Gear Zone (not necessarily in that order).

At the end of this, Sonic gives a final chase to Dr. Eggman, but the doctor ascends to the sky and retreats to the E.G.G. Station Zone, a hover base built by Eggman. Sonic however jumps onto a rising rocket provided by Tails and chases after the doctor in hot pursuit. Onboard the E.G.G. Station, Sonic faces all of the past boss battle machines constructed by Eggman in past zones. After the fourth machine is destroyed, Eggman runs away to a slight depression in the floor; the mad genius rises to reveal his new creation, a rebuild Death Egg Robot. Despite its improvements, Sonic manages to defeat it, and he escapes the now exploding base, and lands in Splash Hill where the ending plays and the adventure ends for now.

Episode 2
In Sonic the Hedgehog 4: Episode 2, Sonic teams up with Tails, as Dr. Eggman joins a formidable alliance with Metal Sonic. After having defeated Dr. Eggman onboard the E.G.G Station, Sonic spent the next few months relaxing from his adventures. This relaxing periode is cut short however when Sonic hears that Dr. Eggman has returned and is up to no good on the neighboring continent. Sonic then seeks out Tails and two of them head out together in the Tornado to investigate the continent and Eggman's newest scheme.

A Colorful Adventure
Sonic returns as the only playable character in Sonic Colors. In the game Dr. Eggman claims to have developed a sense of remorse for his past misdeeds and has constructed Dr. Eggman's Incredible Interstellar Amusement Park, an amusement park made of several planets, to apologize for his actions. Sonic, however, does not believe that Eggman had turned over a new leaf, but that it is just another evil plot, and therefore heads to the amusement park with Tails to stop it.

Once there, Sonic is impressed by the scenic views, but Tails actually thinks that Eggman had a change of heart, but Sonic assures him that Eggman is definitely up to something. While he was checking out the park, he found Orbot and Cubot trying to capture two aliens with nets. While Sonic was not sure on what was going on, he knew that he had to save the two. When he does, the white alien goes inside Sonic and turns Sonic into a laser and zapped away. He later reaches Tails, who is with the white alien he saved and is trying to build a translator so they could understand them. Sonic tells Tails what happened, but Tails finds it hard to believe. The white alien then tries to tell them that Sonic was telling the truth, but the two couldn't understand him. Sonic then decides to find Eggman and figure out what he plans to do with these aliens.

While Tails was busy building the translator, Sonic went out to explore the Tropical Resort and finds Eggman who is gathering up alien. Sonic taunts him for thinking nothing could stop him, but Eggman unleashes the Rotatatron on him, and Sonic destroys it and (unintentionally) sends a piece of it into one of the towers in the process. When he returned to Tails, he had the translator ready (albeit with a few bugs left to work out). Sonic asks the alien what is going on and they learned that his name is Yacker and that he comes from a distant alien race called Wisps, which Eggman has captured. He asks Sonic to save them and Sonic gladly accepts.

Sonic then heads to the nearby planet to investigate and finds a mysterious generator, but is met by the giant robot guarding it. After destroying it and shutting the generator down, Sonic meets Tails and Yacker and asks if Yacker had given any more information (or limericks). Tails tells him that Yacker said that the power Sonic was possessing from the wisps is called Hyper-go-on power, and that Eggman, who the Wisps called "Baldy Nosehair" (which Sonic finds hilarious), is draining them of it for an evil purpose. Sonic thanks them for the information and heads off to the next planet. As he and Tails look for Eggman, Eggman takes them by surprise and tries to brainwash them with his Mind Control Ray that runs on Hyper-go-on energy, but Sonic is saved by Tails. Unfortunately, Tails ends up brainwashed, and Eggman tries to make the two of them fight, but Sonic refuses to fight his friend. Luckily, Eggman runs out of Hyper-go-on energy and Tails is freed. He warned Sonic that he will soon brainwash the entire universe and sends the local giant robot to defeat them before leaving. Sonic then boasts to Tails that he was right about Eggman and battles the robot (though half-hearted as he did not bet with Tails about Eggman).

After the battle and shutting down another generator, Sonic now knows Eggman's plan, but not how to stop it. He learns from Tails and Yacker that Eggman captured the Wisp's planets with tractor beams that hold them above Sonic's world, so if he can destroy their generators, the planets would be free and Eggman would be cut off from his Hyper-go-on energy source. Having already broken two of without knowing, Sonic heads out to destroy the remaining three.

When arriving at Planet Wisp, Sonic is disgusted to see how Eggman transforms the beautiful planet and how he uses the Wisps as fuel and promises the inhabitants to free them. He soon finds the planets generator and the robot protecting it. After a difficult battle Sonic defeats it, but is caught talking to its remains by Tails and Sonic is left pretty embarrassed.

Sonic and Tails continues to Aquarium Park where Sonic fights Admiral Jelly and destroys it, thus freeing another planet. The two then go to the Asteroid Coaster where they work their way into the main center where all of the Wisps were made evil by turning them into "Nega Wisps". Upon this sight, Sonic gets surprisingly serious and asks Tails to excuse him while he finds the next generator. Sonic then battles the Frigate Skullian and breaks the last generator and the factory, thus freeing all of the planets and Wisps. They all then celebrate at Tropical Resort with Sonic break-dancing, thinking it was all over.

Unfortunately for Sonic, Eggman was ready to launch his mind-control weapon on the world, but the broken robot piece from Rotatatron that was unintentionally struck there by Sonic, caused the whole cannon to explode. As the park begins to collapse, Sonic and Tails headed to Eggman's space elevator to get back home. When they arrived there, Eggman showed up in the Egg Nega Wisp, determined to kill Sonic, but Sonic merely taunts him for his attempt to be threatening. Tails tells Sonic that that he doesn't think they can beat Eggman's mech, so Sonic decides to fight Eggman alone and he forcefully pushes Tails into the elevator for his safety and launches him back home. After an intense fight, Sonic manages to defeat Eggman with the help of the Wisps and their special Final Color Blaster. Unfortunately, the destruction of the cannon creates a black hole, one that even Sonic is unable to outrun. As he is caught in the explosion, Sonic sees the Wisps gathering around him and they carries him back to his planet, as well as stopping the black hole. Sonic then gets up and notices that he's on his home planet and is met by Tails. Yacker then appears and thanks them but tells them that he has to go home. Sonic and Tails exchange some high-fives with Yacker, who goes back to Planet Wisp, and sends the other planets back to their original place in the universe.

Déjà Blue; Having a Blast with His Past!
In Sonic Generations, which marks Sonic's 20th birthday, the Sonic of the present, named Modern Sonic, teams up with his younger self from the past, named Classic Sonic, as a new foe called the Time Eater appears and begins interfering with Sonic's history.

In the past of Green Hill, Classic Sonic is exploring when he hears a noise. Suddenly, the Time Eater appears in the sky and he notices it as everything turns white. In the present day, Modern Sonic arrives at a picnic with Tails and all his friends, and wonders what is going on. Then suddenly, they yell "surprise" and reveals that they had made a surprise birthday party for Sonic, who is delighted by the gesture and happily joins. After talking with Tails, Tails gives him a birthday Chili Dog, which Sonic finds delicious.

Suddenly, the Time Eater appears at the party and blows everything away, including Sonic's Chili Dog, much to his disappointment. It then proceeds to suck all of Sonic's friends through time holes, back into different periods in Sonic's history. Sonic goes to attack, but is easily knocked back and passes out. He later wakes up in a White Space and wonders what's going on, but sees some white figures in the distance and decides to check it out.

Once there, Sonic finds Tails and Green Hill in a colorless, frozen state, but after passing through Green Hill, Sonic restores Tails and the area to life. Sonic wonders how Green Hill looked so familiar, but while Tails is curious about this phenomenon, Sonic is more interested in finding their friends. Sonic then quickly sets off to check the colorless Chemical Plant out, but a few seconds later, Classic Sonic appears and Tails mistakes him for Modern Sonic, but simply passes through.

As Modern Sonic (with the unknown help of Classic Sonic) restores Chemical Plant, Sonic sees Tails coming and explains how Chemical Plant feels familiar. Sonic agrees and tells Tails that he feels that he is experiencing déjà-vu. Both Sonics then proceeds through the White Space and restores more areas, along with more of their friends, each unaware of the other's presence.

Sonic later proceeds through a Boss Gate and finds a glass with his younger form at the other side of the glass. Sonic however, mistakes it for a mirror, along with his younger form as his reflection. While looking at himself, Sonic noticed how his reflections' belly is different and gets suspicious. The two then hear Dr. Eggman's voice through a door with Modern Sonic shouting his name. Classic Sonic looks at his older self through the glass and realizes that it was not his reflection. While Modern Sonic is unimpressed by Dr. Eggman's threats, Classic Sonic runs towards Eggman's voice while Modern Sonic was surprised to see his that he "reflection" was actually another "Sonic". Modern Sonic then tries to follow Classic Sonic, but is locked out of the battle.

After Classic Sonic destroys the Death Egg Robot, he sees the same monster that appeared at Green Hill, which kidnaps that time's Dr. Eggman. Modern Sonic later sees Classic Sonic exit the battle and wonders why are there two of him. Tails, who had also met his younger self, realizes the answer and tells Sonic that they are traveling through time and space, which explains why Sonic had been having déjà-vu and that there are two of him. Modern Sonic asks what could do this and the two Tails' think the Time Eater is responsible. The two Sonics then decide to team up and stop the Time Eater.

The two Sonics continue through the White Space and restores the areas, and their friends, one by one. After a while, the Sonics learns from the Tails' that the Time Eater's actions rips space and time apart, and damages the world, by sending damaged areas from different times to the White Space. The Sonics also realize that the faster they go through these areas the more of space and the timeline will be restored.

After Modern Sonic defeats Perfect Chaos, they witness the Time Eater being repelled by a Chaos Emerald and they decide to collect all seven emeralds by restoring more space. Despite the tasks lying ahead of them, both Sonics is thrilled by the adventure. As they finish restoring the areas and their friends, one of the Chaos Emeralds appears, and both Sonics race after it. Modern Sonic however, due to being more experienced, gets the emerald first by using a Sonic Boost, and Classic Sonic is amazed by that move. After Modern Sonic beats the Egg Dragoon with Eggman inside, Sonic taunts Eggman, who was sure to win this time, and tells his past self how he always defeats him. However, the Time Eater strangely comes again and kidnaps Dr. Eggman once more, leaving them more confused.

The Sonics eventually collects all seven Chaos Emeralds and confront the Time Eater in the Center of Time. As Modern Sonic tells it to give up, Dr. Eggman reveals himself as the one controling the Time Eater, much to Sonic's disappointment. Suddenly Dr. Eggman past self, Classic Eggman, reveals himself as being in league with Modern Eggman, and Modern Eggman explains that he plans to use the Time Eater to erase Sonic from the timeline so that he would be victorious in the present. Modern Sonic however, remains unconcerned as he always beats Eggman and now has another of himself to support him. The two Sonics then try to fight them, but they get smashed and knocked out by the Time Eater. As the Sonics are weak and passed out, they get support from all of their friends, allowing the Chaos Emeralds to activate. The two them then awakens, determined to put the fight to an end and transforms into their super forms. The two then defeat the Eggmans, their robot and their plan, and return back with their friends to where Sonic and his birthday party left off.

During the party, Modern Sonic thanks Classic Sonic for his help and hopes he learned a few tricks, and Classic Sonic replies by demonstrating one of Sonic's newer abilities, the Sonic Boost, but slightly fails to keep up. Sonic claps for his younger self, saying that he will get better and as Sonic's and Tails' younger forms heads back to their time, Modern Sonic says to Classic Sonic "Hey Sonic! Enjoy your future. It's going to be great!".

Other Game Appearances
Sonic has also been featured in games of many genres other than 2D and 3D platform games. The first of these was a pinball game, Sonic Spinball (1993), which expanded upon the pinball sequences in the first two platform games. Sonic has also appeared in "2.5D" isometric platformers (Sonic Labyrinth, Sonic Battle and Sonic 3D Blast), racing games (Sonic Drift, Sonic Drift 2, Sonic R, Sonic Riders, Sonic Riders: Zero Gravity, Sonic Free Riders, and Sonic & Sega All-Stars Racing.) and fighting games (Sonic the Fighters ,Sonic Battle, and Super Smash Bros. Brawl ). He also, for the first time, teamed up with his video game rival, Mario, in Mario & Sonic at the Olympic Games. They would also get together again in Mario & Sonic at the Olympic Winter Games, Super Smash Bros. Brawl, and Mario & Sonic at the London 2012 Olympic Games.

Cameos
Video games such as Dr. Robotnik's Mean Bean Machine, Tails Adventure, Knuckles Chaotix and Shadow the Hedgehog starred supporting characters of the Sonic series; in some of them Sonic had a cameo role. The hedgehog has also made cameo appearances in numerous other Sega games such as Daytona USA.

Personality
Sonic has been described as being "like the wind"; he is always on the move, always moves forward and is noted for being free-spirited and adventurous. He values freedom above all else and lives his life according to his own rules and simply enjoys traveling the world (and beyond) while searching for adventure.

He mainly prefers to simply be called by his name and not any fancy title; in his encounters with Princess Elise and Cream the Rabbit (both called him "Mr. Sonic"), Shahra the Ring Genie (who called him "Master"), Caliburn the Sword (who called him "Knave", though Sonic was especially annoyed by this), and Erazor Djinn (who kept calling him "Filthy rat", though it might just be an insult), he insisted that they merely call him "Sonic".

Sonic is mostly laid-back, cool and enjoys relaxation and firmly stands for freedom, but he is never one to rest in the face of injustice or oppression. He hates evil in all its forms and can easily be riled up about it; if he witnesses someone being opressed, are suffering from injustice or are simply depressed or despairs due to others' actions he will not show a moment of hesitation and will instantly step in to help those in need, even if it means that his actions will be met with contempt, as stated in Sonic and the Black Knight.

Sonic is extremely benevolent though he has been described as quick-tempered occasionally. Despite this, he always remains loyal to his friends, always keeps his word and he willingly puts himself at risk to help others, taking on any challenge that confronts him without hesitation, though he usually sees his heroics and fighting evil as an opportunity to have fun, making him somewhat of a thrill-seeker. However, in times of crisis, he focuses entirely on the task at hand and sees it as truly serious with no real fun involved. Despite this, Sonic's cocky, upbeat demeanor will remain unchanged, being foregone in only the most dire of situations. Sonic is shown to have a remarkable capacity to forgive, as seen in Sonic the Hedgehog (2006), when he quickly forgave Silver and accepted his help in saving Elise in their third encounter, despite that Silver tried to kill him, twice.

Following his free-spirited, adventurous and speedy nature, Sonic never dwells on the past, or whatever sad or hurtful things that has occurred on his adventures for too long and always takes them in stride, never allowing them to weight him down. Such instances is when Emerl died, the disappearance of Shadow or when he had to say goodbye to Chip who had to be sealed in the planets core; each time Sonic merely remains calm while paying his respects and response with a positive attitude afterwards. Instead, he choses to live in the present and always looks forward to his next adventure, while holding no regrets for whatever has transpired, as long as it turned out well.

As shown several times, Sonic is very confident in himself and has a big additude with just a large ego to match it, making him sassy and quick-witted. He often jokes around to light the mood of a situation, but will also glady take any opportunity to tease and mock his opponents in battle and takes many of the lesser situations and opponents he faces lighthearted. This trait is most prominent in Sonic Colors where Sonic remains cool and laid-back, not behaving seriously in any of the scenes. He is usually seen around cracking up jokes and talking to himself. Sonic shows a lot of sarcastic attitude through his gestures but then enjoys any challenge that passes him. He likes to talk to robots (the boss-fights in the games) usually teasing them and even acting like a waiter to one of the robots even though he knows that they can't talk. Talking to robots is something that has not been shown in any game and he can even talk to them if they are completely broken. He was also embarrassed when Tails found out that he talks to broken robots that "can't actually hear him".

Sonic is not generally modest when it comes to his abilities and is regarded as being very proud and a world renowned showoff. On the other hand, he can also be quite the gentleman and he has been known to show some form of modesty when taking compliments. This is shown in Sonic and the Secret Rings where Sonic prefers not to be called "Master", and where he is referred to as the "Legendary Hedgehog" ("Me? Legendary? You've gotta be kidding! You're gonna make me blush!").

Sonic's taunts and confidence easily portray that he is smug. He is also very stubborn, as shown in the end of Team Sonic's story in Sonic Heroes. After narrowly escaping Eggman's exploding ship, Knuckles exclaims, "Boy, talk about cutting close!" to which Sonic replies, "Not really..." this implies Sonic is too stubborn to admit a task is difficult for him, but after being teased by Knuckles, Sonic admits he needed Knuckles' and Tails' help, to Knuckles' obvious great surprise. In contrast however, Sonic can sometimes be overconfident in his abilities; for example, when Merlina stops him from attacking the Black Knight, he is irked and asked why she did so, positive that he could have defeated him.

Sonic is also known for indomitable will (which no doubt goes hand in hand with stubbornness), his absolute confidence and never-waving faith in himself and his will to keep on fighting surpasses his actual ability to keep on fighting. An example of this can be seen in Sonic and the Black Knight, where Sonic continues to try to fight Merlina despite being unable to reach her through her force field shield, being hit repeated times so he is badly hurt and exhausted, and having his sword broken as he attempted to parry Merlina's attack. Sonic's friends plead him to give up, but he refuses ("It was never about chivalry for me. I've just gotta do what I gotta do, that's all...").

A very noticeable trait of Sonic is for his fondness for the beauty of nature. Ever since the first Sonic game in 1991, Sonic has been shown to be a protector of nature. In several games like Sonic Rush Adventure, Sonic 06, Sonic Colors shows Sonic appreciating scenic views. His love for nature is defined in Sonic Colors where Sonic appreciated Dr. Eggman for making Tropical Resort a beautiful view, and when Sonic reached Planet Wisp when Sonic showed an emotion of anger and rage when he found out that Eggman was polluting the planet which was filled with beautiful plants, this also marks the only time in which Sonic was shown serious and angry in Sonic Colors. His anger for Planet Wisp being polluted was put further when he said, "That's pretty low, even for a sleazeball like Eggman!" meaning that he thinks that Eggman polluting a scenic planet is even more evil than Eggman himself. In Sonic the Hedgehog (2006), Sonic is shown to have a fondness for locations that are filled with flowers, trees and other kinds of plants. Sonic appears to be an introvert; after spending time with his friends, he seeks some alone time and relaxation and then gets back to his friends.

Sonic Unleashed's booklet states that his personality is "A juxtaposition of kindness and ferocity, as, on one hand, he does all he can to snuff out evil, but he can't look away when someone is in trouble." Sonic Unleashed also has sidequests in which Sonic the Werehog is trying to convince the Elder Gregorios in Apotos that he is Sonic the Hedgehog. To prove it, Sonic undergoes a test of speed, which involves him getting a pair of glasses for the Elder in a certain time limit; a test of courage, by protecting the Elder from minions of Dark Gaia; and a test of selflessness and kindness, which involves Sonic obtaining a book for the Elder out of kindness.

It has also been shown that Sonic will try to hide pain, fear - unless Amy gets angry, during which Sonic will show obvious nervousness or even fear- or exhaustion. It is also shown that Sonic faints after some adventures(An example of this is in Sonic Unleashed and Sonic Colors). It has been revealed that Sonic loves and takes great pride in his speed, and that he takes insults towards his speed rather personally.

It is to note that regardless of the countless foes he has fought throughout the series, he bears no noticeable ill will to any of them, but rather he admires how powerful some of them are and how much fun they have given to him. An example of this is seen when Metal Sonic is defeated and Sonic tells him that he is open for a rematch. Most notable towards Dr. Eggman, whom has constantly tried to destroy him to complete his schemes, however Sonic is satisfied with merely stopping him, also in occasions where Eggman helps Sonic and co. to save the world (although for his own interests, mainly because he couldn't take over the world, if it's destroyed) he never rejects his help.

Despite his thrill-seeking, hyperactive, and smug demeanor, Sonic has shown many times to be much more insightful than he usually lets on. In the earliest display of this insight would be in Sonic Adventure, where Sonic was able to understand how simply resealing Chaos in the Master Emerald while Chaos was still suffering from all of its rage would solve nothing in the end. Other instances include in Sonic the Hedgehog (2006), in which Sonic was able to give Elise valuable and comforting advice, and in the end of Sonic and the Black Knight, where he was able to give Merlina similar words of encouragement and comfort. This insight, combined with a charismatic personality, allows Sonic to get along with virtually anyone he meets, even if at one point they were his enemies.

The Japanese version of Sonic Advance 3 strategy guide, Sonic Unleashed, and Sonic and the Black Knight states that, Sonic's favorite food is chili dogs. He enjoys music, but seems to have an special interest in rock music. Some official character art and a television commercial for Sonic Adventure suggests that he has a personal hobby as a Disc Jockey. Furthermore, it is displayed in Sonic Rush that Sonic also enjoys break dancing as it is one of his primary ways for filling up his Rush meter. His battle moves in Sonic Battle are also based on break dancing, as mentioned in the attack descriptions. He also breakdances in Sonic Advance 3 if he finishes a level in a short-enough time. Lastly, one of his taunts in Super Smash Bros. Brawl is him break dancing and saying, "C'mon, step it up!" He will also breakdance if he gets first place in the Mario and Sonic at the Olympic Winter Games.

Apperances in Other Media
Sonic has appeared in several different media (such as TV series and comics) outside of his mainstream games series. These series often take place in their own unique continuities, which differ greatly from the games in terms of plot, setting, and even Sonic's characterization. Some versions of Sonic from these alternate continuities are listed here.

Television series and Movie
There have been several animated series featuring Sonic.

Adventures of Sonic the Hedgehog
Adventures of Sonic the Hedgehog was the first cartoon to featured Sonic and had a very comical take on Sonic's adventures. In this media, Sonic is a world roaming hero with a lifestyle similar to a tramp, who fiercely defends the citizens of Mobius from the evil schemes of Dr. Ivo Robotnik and his lackeys Scratch and Grounder. One day, he came across a young orphan named Miles "Tails" Prower who he decided to adopt as his younger brother, as the young fox had none to live with and they became as close as a real family. While Sonic has his trademark atttude in this media, he also tries his best to stands out as a responsible role model for the innocent Tails, especially during the Sonic Sez segments.

Sonic the Hedgehog (TV series)
Sonic the Hedgehog (SatAM), originally broadcast on Saturdays on ABC, was broadcast concurrently with the syndicated Adventures series in the United States. The Archie Comics continuity was based heavily on this series and features a similar background for Sonic. In this media, Sonic lived in Mobotropolis with Princess Sally Acorn and the future Freedom Fighters during their childhood until Dr. Ivo Robotnik invaded the kingdom, enslaved the people with the Roboticization technology and took control of Mobius.

Sonic and his friends however managed to escape the tyrant by fleeing into the Great Forest where they built a village named Knothole to hide from Robotnik. There Sonic, Sally and the others then formed the Freedom Fighters and began a ten year long battle with Dr. Robotnik to take back their planet, with Sonic being one of the main leaders and their primary agent.

Sonic Underground
Sonic Underground, a show in the US, United Kingdom and France, ignored the continuity of the previous series and games and instead introduced two siblings and Sonic's mother, named Sonia, Manic, and Queen Aleena respectively. In this media, Sonic was born as the heir to the throne of Mobius, along with his siblings, Manic and Sonia. Shortly after their birth however, their mother Queen Aleena was dethroned by Dr. Ivo Robotnik and they became wanted, but the Oracle of Delphius prophecized that Aleena and her children would one day defeat Robotnik, but only if she left her children in the care of others until then.

Sonic himself was left in the care of a regular family, but during his early childhood his adopted family was captured and roboticized. He then joined his Uncle Chuck and the Freedom Fighters in the battle against Robotnik over many years. One day however, Sonic was approached by the Oracle who revealed his origin and family. Sonic soon after reunited with his siblings and together they formed the band Sonic Underground where they fought Robotnik while searching for their mother.

In this media, Sonic possess a medalion that transforms into an electric guitar/laser rifle.

Sonic the Hedgehog: The Movie
Additionally, there was an OVA movie that featured Sonic, Tails, Knuckles, Dr. Robotnik and Metal Sonic. In this movie. Sonic and Tails lived on Planet Freedom, but were one day called by Doctor Robotnik to battle an evil robot named Metal Robotnik and save their planet from destruction. This was however a trick on Robotnik's behalf so the evil doctor could copy Sonic's data into his Hyper Metal Sonic robot. After the doctor succeded in his plan, Sonic and his friends tried to stop this metallic copy from destroying the world.

Sonic X
The latest animated Sonic television series is the anime Sonic X. In this media, Sonic originally lived on a parallel version of Earth in another dimension. During one of his battles with Dr. Eggman however, a massive Chaos Control blast occurred and Sonic, his friends and Dr. Eggman were transported to the human world. Shortly after arriving, Sonic nearly drowned in a pool, but was saved by Chris Thorndyke, who Sonic became friends with. Over time, Chris came to have a strong bond with Sonic as he lived a lonely life.

Sonic eventually settled down on this new world with his friends and became a famous hero among the human population as he and his friends protected the world from Dr. Eggman as the doctor attempted to rebuild his Eggman Empire in this new world. Like the other television series, the show had an original storyline not present in any of the games, although it can be viewed as an elaboration upon the Sonic Adventure games' storylines. Eventually, Sonic and everyone from his world were forced to return home as their presence threatened to freeze time. Before Sonic could return home however, he was kidnapped by Chris who did not want him to leave, but Sonic eventually made Chris come to terms with his feelings and Sonic returned home.

In season 3, Sonic teamed up with his friends and Chris, who had just arrived in Sonic's dimension, to fight the Metarex, an alien race of cyborgs that was a threat to the safety of the entire galaxy. With everyone's aid, Sonic managed to defeat the Metarex and their leader Dark Oak and saved the galaxy. Upon returning to his home planet, Sonic had his goodbye with Chris who returned to his world and Sonic himself went back to his normal battles with Dr. Eggman once more.

Books and comics
Sonic's first comic appearance was in a promotional comic printed in Disney Adventures magazine, which established an origin for Sonic involving the transformation of kindly scientist Doctor Ovi Kintobor into the evil Dr. Ivo Robotnik. Numerous British publications, including "Sega handbook" Stay Sonic (1993), four novels published by Virgin Books (1993–1994) and the comic book Sonic the Comic (1993–2002) used this premise as their basis.

The American comics published by Archie Comics, Sonic the Hedgehog (1993—present), Sonic X (comics) (2005—2009) and Sonic Universe (2009-present) are based on the settings established by earlier animated TV series, the ABC Sonic the Hedgehog (SatAM) cartoon and the Sonic X anime respectively.

In Japan, Sonic manga have been published, and there is currently another one being published based on Sonic Unleashed featuring Chip.

There is also released comics, Sonic The Hedgehog Archives, which presents the rare comics with a premium format.

Sonic the Hedgehog (Archie Comics)
In the Archie comics, Sonic is the most famous hero on Mobius. He is best known for his defeat of Robotnik Prime and his heroic actions preventing the Xorda from destroying Mobius and its solar system. Raised in Mobotropolis before Robotnik Prime's coup, Sonic was an average child except for his abnormal speed. Sonic lost his parents to the roboticizer and was taken in by his Uncle Chuck until he too was roboticized. During Robotnik Prime's coup Sonic and a few others were herded to Knothole Village by the Original Freedom Fighters. It was from them that Sonic got the inspiration that would one day make him a hero.

As Sonic developed his incredible speed, his attitude became legendary. Irreverent, confident, impatient, and energetic, Sonic fought constantly to overthrow Robotnik Prime and continues the fight against his successor, Robo-Robotnik (later renamed Dr. Eggman).

In addition to his uncanny speed, Sonic has the ability to absorb Chaos Energy. Absorbing a great amount of this energy causes him to transform into Super Sonic. As Super Sonic, all of his natural abilities are enhanced and he gains the ability to fly, among other strange powers. His skin and eye colors change to yellow and red respectively, and he takes on an aura of yellow energy. It has happened also that Sonic has transformed even further into Ultra Sonic. Ultra Sonic is even more powerful and has the ability to adapt to his surroundings by taking on new forms.

After the Xorda attack, Sonic was teleported into space, where he spent a couple months trying to return to Mobius. But when he returned, a whole year had passed, and things were very different. Sonic is still not completely adapted to the changes he has seen.

Sonic the Comic
In Sonic the Comic, Sonic was once an ordinary brown (though still fast) hedgehog on the planet Mobius. He encountered a kindly scientist named Doctor Ovi Kintobor, who performed experiments on his speed. An explosion resulted in his spines fusing together and turning blue. A later experiment, involving Kintobor's attempts to rid Mobius of evil, transformed the good doctor into Ivo Robotnik. After several unsuccessful attempts to take over the world (as depicted in the first two Sonic games), Robotnik finally managed to conquer the planet by sending Sonic six months into the future. On his return, Sonic took it upon himself to form a group of Freedom Fighters to depose Robotnik, which they finally managed to do in the series' landmark 100th issue.

As in other continuities, Sonic is aided in his adventures by his loyal sidekick Tails, as well as Amy Rose and original characters Porker Lewis, Johnny Lightfoot, Tekno the Canary and others. He has a friendly, though still quite intense, rivalry with Knuckles the Echidna, who frequently accuses Sonic of bringing trouble onto his Floating Island.

Sonic can turn into Super Sonic in this continuity without exposure to the Chaos Emeralds (because of a dose of radiation he received when the Emeralds were first brought together), but in this form he is out-of-control, bordering on psychotic, and he attacks friends and enemies alike. The two were separated for an extended run, but re-united in the series' final story arc.

Reception and legacy
As Sega's mascot and one of the key reasons for the company's success during the 16-bit era of consoles, Sonic is one of the most recognizable video game characters in the world. In 1996, Sonic was the first video game character to be seen in a Rose Parade. Sonic is also the first of two video game characters to have a balloon in Macy's Thanksgiving Day Parade (the other being Pikachu).

Sonic was one of the three game characters inducted on the inaugural Walk of Game class in 2005, along with rival Mario and Link. One of a class of genes involved in fruit fly embryonic development, called hedgehog genes, has been named "sonic hedgehog" after the character.

As Sega's mascot, Sonic has also been used as a symbol for the company's various sponsorships. Between 1993 and 1997, Sega sponsored the JEF United Ichihara Chiba football team, during which period Sonic appeared in the team's uniform. During the 1993 Formula One championship, Sega sponsored the Williams Grand Prix team, which won the Constructors' Championship that year, as well as the team's lead driver, Alain Prost, winning the Drivers' Championship. Sonic was featured in the cars, helmets, and rival McLaren used to paint a squashed hedgehog after winning races over Williams. The 1993 European Grand Prix featured a Sonic balloon and Sonic billboards, and the race's trophy was in the shape of a hedgehog. Sonic also appears on some versions of the willow video store logo. Sonic is more recognizable for people than Mickey Mouse according to a poll.

On the 21st October 2008, Sonic was voted the most popular video game character in the UK with a 24% vote. His old rival Mario came second with 21% of the vote.

Cameos/popularity
Sonic has proven to be an extremely popular character. After the first game, Sonic the Hedgehog (1991) came out, Sonic became a well-known and very familiar character, even at a time beating Mickey Mouse. After having been around only 2 years, he had already surpassed Nintendo's Mario in popularity according to a June 1993 Q-Survey in Gameplayers magazine. As a result of this popularity, he has been referred to in various parts of culture.

Voice acting
The earliest voice of Sonic was Takeshi Kusao in the game SegaSonic the Hedgehog, a June 1993 arcade release starring Sonic the Hedgehog, Mighty the Armadillo, and Ray the Flying Squirrel.

In Sonic CD, Sonic actually had a few voice clips, who was voiced by Keiko Utoku at the time, in which he would say, among other things, I'm outta here! if the player stood still for 3 minutes, and Yes! if the player obtained a 1-up.

The original American voice actor was Jaleel White, in Sonic the Hedgehog: The Animated Series (SatAM as known to fans). In Sonic the Hedgehog: The Movie, Sonic's voice was played by Martin Burke.

Starting with the 1998 game Sonic Adventure, all of Sonic's video games feature voice acting. Sonic was played by Junichi Kanemaru, who later went on to play Sonic in the Japanese version of Sonic X. Ryan Drummond performed the role of Sonic in Sonic Adventure and continued to play the role for several games. Information taken from the credits of both Sonic Adventure games, the Sonic Advance series, and Sonic Heroes. 4Kids Entertainment decided not to use Drummond's voice in their US/UK dub of Sonic X, instead choosing their own Jason Griffith. Despite this, Drummond continued to provide the voice of Sonic in the series until 2005, when Sega replaced all their Sonic voice actors with their 4Kids counterparts, in order to keep his voice the same in all media forms. Effectively, this meant that beginning with Shadow the Hedgehog and Sonic Rush, Jason Griffith became the official game voice actor for Sonic the Hedgehog and Shadow the Hedgehog (and Jet the Hawk in Sonic Riders). This has been a controversial decision among fans of the Sonic Adventure voice cast.

As from 2010, SEGA had announced that they have changed the whole cast of the active characters of the franchise (sans Eggman), replacing Griffith with Roger Craig Smith.

Abilities
Sonic is known best for his speed, with the ability to run at speeds greater than Mach 1 (known from Sonic X), which is at the blistering speed of 768 miles per hour. This is evident in many games, where Sonic is recorded to run at speeds faster than 765 mph. In Sonic Unleashed, the checkpoint posts (Star Posts) also act as radars that clock Sonic's speed when he passes them. Due to the fact that his speed increases the longer he's boosting, it's possible for the checkpoint posts to show Sonic's max speed in-game, being able to clock him going at over 2,500 mph. It is also stated in the Sonic Adventure DX manual that "He's the world's fastest, hypersonic hedgehog" which is at a staggering speed of 3,840 mph. He is occasionally referred to as "the fastest thing alive," and can run backwards at full speed just as well as forwards, as shown in the Team Sonic opening cut-scene of Sonic Heroes. Due to such speed, he is able to scale right up the walls of buildings, or similar structures, and can also run right over water.

His speed does not seem to have certain weaknesses in that recklessness (the possibility of crashing into unintended targets) and "straight-line only" concepts are invoked, which implies that Sonic relies on his animal instincts to control the line of his running paths (and possibly for his Homing Attacks as well). Sonic is also shown to be able to run in full tight circles, thus is not exposed to the weakness of only being able to run fast in straight lines. Should he be running at fast uncontrollable speeds, he can use the Sonic Drift to properly control his momentum, and even crash into foes with it.

In line with his speed, Sonic has displayed amazing feats of movement and has reaction time to match it. He possesses great acrobatic skills and agility, alongside with astonishing reflexes, making him able to avoid large and small obstacles with precise jumps and delicate movements, such as his Quick Step, despite the speed they are incomming at, and when launched into the air, he can perform several airborn tricks before finally landing on ground. He has also shown on several occasions that he can jump incredible long distances, up to several hundred meters, possibly by applying his speed to his jumps.

It is unknown how much faster Sonic can run beyond Mach 1, although it is variously assumed that he can. In Sonic Battle, it is stated that he can move several times the speed of sound and in Emerl's story, Sonic takes on and defeats the Gizoid in under 30 seconds, before the Final Egg Blaster fires in that time. Also in Sonic Battle, Sonic possesses the ability to heal himself, presumably by vibrating his molecules, and from the same game can also launch shockwaves by spinning in his spinball form at high speeds. It is also believed that Sonic can move faster while in spinball form than running, possibly even reaching the speed of light due to the various proofs, such as in Sonic Adventure 1/2 and Sonic Heroes, where he could use the move Light Speed Attack which, stated by Tikal, attacks enemies at Light Speed. Omega also stated in Sonic Colors (DS) that with Sonic's current progress, he would surpass the speed of light.

Many of his abilities are variations on the tendency for hedgehogs to roll into tight balls for protection. Since his introduction in the first Sonic the Hedgehog, Sonic's primary offensive maneuver is the basic Spin Attack (or "Sonic Spin Attack"). As Sonic jumps or runs, he curls up and spins into a spiky ball when in motion that can damage, destroy, mow down, or burrow through many obstacles or foes. Later games in the series expanded on this basic attack. Two of these enhancements are now basic moves: the Spin Dash was introduced in Sonic 2 and involves Sonic spinning on the spot before blasting off at full speed, and the Homing Attack, officially introduced in Sonic Adventure, although unnamed variations of it appeared in Sonic 3 & Knuckles and Sonic 3D Blast, in which Sonic dashes in midair toward a target (can be implyed to be guided by his instincts so that Sonic won't miss). Since AoSTH and SatAM, Sonic can also execute a ‘triple spin’, where he curls up into a ball and spins around quickly, like a buzz saw, and can burrow through the ground or a wall, depending on what it’s made from.

The Super Peel Out, or Figure 8 Dash, made its debut in Sonic CD, but since has only had minor recurrences in the Archie Comic series and anime. In the Figure 8 Dash, Sonic stays pivoted in one place and his legs move fast enough to create the illusion of an infinity symbol (more correctly a Möbius strip) beneath him in red. He holds this and then blasts forward.

Another technique, the Blue Tornado (from Sonic Heroes) or Sonic Wind (from Sonic Adventure 2) is when Sonic jumps into the air, and creates a whirlwind by circling a particular spot at high speeds. A similar attack called "Whirlwind" appeared in Sonic Chronicles: The Dark Brotherhood. Other such special moves that Sonic has in this game are 'Axe Kick,' and combination attacks between Tails, Knuckles, and Amy. Sonic has also demonstrated the ability to harness the power of the Chaos Emerald for his own use. With one Chaos Emerald Sonic can warp time and space with Chaos Control, and occasionally gains a boost in power.

One of Sonic's newest signature moves is the Sonic Boost, a technique where he can increase his speed futher and turn himself into projectile by moving at such high speeds that he destroys any enemy caught in his path. He does not even need to have contact with the ground in order to execute the move as seen in Sonic Generations, and can use it to practically fly immense distances through midair. Similar to his healing ability in Sonic Battle, Sonic seems to be able to displace almost anything with his supersonic attributes. Also in Sonic Generations, he can even make objects accelerate faster with no need to expend power, as on Planet Wisp he can land on moving coal carriers and make them carry at a higher speed.

Sonic also possesses an indomitable force of will; even in situations where most others would give up and resign themselves to defeat or imprisonment, and in situations where he is severely outnumbered and outgunned, he always forges on, never loses faith in himself and never quits. This character trait is most noticeable in Sonic Unleashed, wherein, thanks to his will, he is one of the few people on the planet who is immune to the influence of Dark Gaia. This is also shown in Sonic Chronicles: The Dark Brotherhood, where the Voxai Overmind attempts to use mind control on Sonic, and he resists when all other characters fail to do so. This may also be because he is in possession of a Chaos Emerald filled with the Overmind's power. It appears once more in Sonic and the Black Knight, where he continues to fight Merlina despite having Caliburn broken in half and beaten to the point where he could barely stand. He presumably performed a similar feat in Sonic Battle when facing Ultimate Emerl. Emerl was vastly superior to Sonic in every aspect: he has the abilities of every character, all 7 Chaos Emeralds and the power of a star system-busting cannon (Final Egg Blaster). Thanks to Sonic's indomitable force of will, he was able to perform the impossible: defeat an opponent who is superior to him in almost every way possible. The only time his will didn't work was in Sonic Rivals 2 when he got possessed by the Ifrit in Tails' story scenario. It's safe to assume that if he does get possessed, he does all he can to regain control.

It is assumed that Sonic can control the strength or hardness of his quills. They appear to be extremely hard like buzzsaw blades when he is in spinball form, capable of shredding through several layers of reinforced steel to just about anything with enough speed. When he is not in ball form, they appear soft and flimsy like rubber. In Sonic Heroes, his quills (and body) are durable enough to slice through battleships without even moving at the speed of sound. In Super Smash Bros. Brawl, he can temporarily increase the durability of his quills to hit opponents in his Up Throw. In this move, he throws up an enemy, goes into a push-up type pose, and flares up and hardens his quills for the enemy to land on.

Sonic has several times shown to have great resilience to physical damage. He can survive being caught in a crossfire from all angles by Eggman's robots and is only knocked out briefly by it and he can run through several robots with his fist in front without showing any sign of pain or injuries. It is also worth noting that for nearly all the battles Sonic has been through, he has never been crippled or displayed any seriuos injuries. It is also shown that he can survive numerous free-falls from space, in various Sonic games. In Sonic Adventure, he fell face first from a high point in the atmosphere and merely shook it off after the crash of the Tornado (although he luckily fell into soft sand), and near the end of his story fell once again from about the same height from the Egg Carrier into the Mystic Ruins jungle. In Sonic Unleashed, he (as the Werehog) survived atmospheric reentry unharmed; however, he was stopped in mid-air right before landing by a shield of light (most likely it was Chip) and was stuck in the ground for a few moments. He accomplished this feat in Sonic the Hedgehog 2 as well as Sonic & Knuckles in his normal form at the end of both games (assuming the player didn't gather the Chaos Emeralds prior to beating the game). This can also relate to, gameplay wise, Sonic having stacked rings up then getting hit by a possibly hard attack, with Sonic recovering somewhat fine from said impact.

Despite not having received any known training in combat, the many years of battles Sonic has been through has made him a skilled fighter and strong combatant in hand-to-hand combat and he can go up against others who have spend most of their lives training for battles. It is possible that Sonic might actually have superhuman strength (though nothing in comparison to Knuckles'). Sonic's Spin Dash and other spin forms are strong enough to cut through enemies (though not all shields), burrow through the ground, tear robot parts from their body with brute force alone, smash through surfaces by stomping, or break down walls though it is debatable if the attack's main power is from his supersonic speed or superhuman strength or a combination of both. A lot of moves Sonic performs in fighting games has him use his feet and legs more than his hands which suggests that Sonic's legs are more powerful than his arms. Sonic's Back-Grab in Brawl has him backflip backwards (while holding the opponent), land on the ground, and kick the opponent at a decent knockback. His forward smash consists of Sonic swinging his arm around for a short time and then releasing a charged punch (which might resemble his buzzsaw type attacks). This attack is one of his most powerful smash attacks in terms of knockback. Also as a nod to his footwork, Sonic also at times like in Sonic Battle, applies breakdancing to his combative footwork, especially in his Sonic Flare attack.

It is safe to say that Sonic is far stronger, faster, and more skillful then he lets on. Only in truly bleak situations does he reveal his true power - his fight with Ultimate Emerl, the Ultimate Gizoid, and his temporary ruthlessness as Dark Sonic are prime examples of this. Sonic may be able to defeat practically any enemy if he was to fight seriously from the beginning. It would appear that his cockiness, overconfidence and unwillingness to fight at full power stop him from truly being considered the most powerful character in the series. Also, Sonic is often reluctant to use his Chaos Powers, and relies on his speed more.

In the Sonic Riders series, Sonic has proven himself as a world-class Extreme Gear rider and is able to go head-to-head with the best Extreme Gear riders the world has to offer, namely Jet the Hawk. It would appear that Sonic has a natural talent for Extreme Gear riding, as he quickly grasped the controls on his first try and can perform several advanced techniques, despite being self-taught. After the events of Sonic Free Riders, Sonic can be considered the best Extreme Gear rider in the world, as he was able to beat Metal Sonic, who at that point possessed all the data and skills of the world's best Extreme Gear riders, in a race.

Even though he does not prefer to use weapons in combat (mainly dissing firearms as said in Shadow the Hedgehog), Sonic is shown to excel in swordsmanship as seen in Sonic and the Black Knight. Even after having just picked up a sword, Sonic was able to slay a dragon using a sword alone and after receiving formal training from Caliburn, Sonic becomes capable of going up against the best knights in the world of King Arthur in duels with swords, such as Lancelot, Percival and even King Arthur himself. By using his speed and moves in line with his swordplay, Sonic can make quick and swift slashes and becomes a buzzsaw when spinning around with his sword, making him a dangerous force to be reckoned with.

In Sonic Colors, Sonic is able to utilize a very powerful colorful energy called Hyper-go-on Energy, from which Sonic can absorb from the Wisps, that gives him addition abilities. This includes Sonic turning into a drill, a laser or even a fireball.

In Sonic and the Secret Rings, during Dinosaur Jungle, Sonic mentions that his quills can sense danger, before being attacked by a dinosaur.

POW Moves
In Sonic Chronicles: The Dark Brotherhood Sonic's POW moves are purely offensive attacks that involve using his speed to create wind currents that can damage the opponent or launch himself as a projectile while in spinball form. These are:


 * Axe Kick: Sonic spinballs into an enemy, then follows up with a powerful air-kick.


 * Whirlwind: Sonic performs a Tornado move, damaging everyone caught inside.


 * Blue Bomber: Tails lifts Sonic up, then throws him onto a target. Sonic then rebounds and hits the target a second time, leaving it weakened.


 * Fastball: Amy uses her hammer to hit a spinballing Sonic into a foe three times, rendering it sluggish.


 * Triple Tornado: In a variation of the aforementioned Whirlwind move, Sonic, Knuckles, and Tails get propelled in the air in a Tornado move, then fall down and hit all enemies. This may leave targets Sluggish.


 * Hail Storm: Knuckles, Tails, and Amy smash a spinballing Sonic at a single target, potentially stunning the foe.

Transformations
During his adventures, Sonic has shown the ability to enter a number of different transformations (usually super transformations) to assist him in his toughest battles. This is usually done by using certain objects that possesses great power, or absorbing different varieties of energy. With these transformations, Sonic usually undergoes a physical alteration, gets his speed and strength increased and gains new abilities that match the theme of the transformation. While using these transformations, Sonic's personality and character usually remains the same, but some transformations has been known to affect his personality, giving him more darker traits

Super Sonic
By using all seven Chaos Emeralds, Sonic can initiate a super transformation called Super Sonic. This is by far Sonic's most frequently used transformation. In this state he can fly, is faster, stronger and nearly invincible. He does, however, need rings to maintain this transformation or else he will revert to normal.

Hyper Sonic
Sonic also possesses an extended and more powerful form of Super Sonic, called Hyper Sonic, which he can assume with the seven Super Emeralds. This form basically shares the same powers and traits as Super Sonic, but they are all upgraded and are more powerful than Super Sonic's.

Darkspine Sonic
In addition, by harnessing the power of three of the World Rings in Sonic and the Secret Rings, it allows Sonic to become Darkspine Sonic, a powerful form powered by his negative emotions. In this state, Sonic can fly, have greater strength, unlimited use of the Soul Gauge powers and traits of fire-based attacks. Because of the negative emotions from this transformation, Sonic becomes slightly more sinister and violent.

Excalibur-Sonic
In Sonic and the Black Knight Sonic gains another super transformation: Excalibur-Sonic, by using the power of the Sacred Swords. This form grants him a golden armor with a red cape, the ability to fly, greater strength and the power to wield the legendary sword Excalibur.

Sonic the Werehog
In Sonic Unleashed, Sonic unwillingly gains the power to turn into a werewolf-like version of himself at night time by accidently absorbing the energies from Dark Gaia. In this state, he loses his trademark speed, but he gains super strength, the ability to stretch his arms, and limited energy manipulation. While Sonic's strong will prevents him from going crazy like the other people affected by Dark Gaia, he does gain some minor feral behavior.

Ultra Sonic
In Archie's Sonic the Hedgehog, Sonic is able to become Ultra Sonic by using massive amounts of power (such as a vast amount of Power Rings or a Super Emerald). In this form Sonic is able to fly and can control non-living matter on an atomic level, allowing him to manipulate the elements. He can also adapt his physical form and powers to the environment, allowing him assume forms such as Polar Sonic, Solar Sonic and Eco Sonic.

Dark Sonic
In the episode "Teasing Time" in Sonic X, after witnessing Chris's injuries and Cosmo's fright, Sonic is blinded by rage and absorbs the negative energies from a nearby pile of fake Chaos Emeralds, becoming Dark Sonic. In this form Sonic becomes more angry and brutal than seen in the series before. He displays the same powers as Super Sonic, but in a more extreme, violent and intense way, such as when he brutally ripped apart the two prototype Metarex soldiers.

Weaknesses
Sonic is incapable of swimming, which causes him to sink like a stone in water, probably mainly due to his great body weight for his size and narrow limbs or possibly due to his presumed aquaphobia (or he just does not know how to swim). Although, if hitting the water while running, he can dash across the water's surface, completely bypassing the hazard (an exception being in Super Smash Bros. Brawl, in which all characters are able to swim, but he can only swim for a brief period of time before drowning). In most media, he is shown completely avoiding water. In Mario & Sonic at the Olympic Games and Mario & Sonic at the London 2012 Olympic Games, when Sonic competes in Aquatics events, he is the only character who wears a life preserver. However, in Super Smash Bros. Brawl, Sonic can swim without a life preserver, though he seems to be flopping like a fish when swimming, unlike the other characters. Although an exception of Sonic's poor aquatic abilities is in Sonic the Hedgehog [1991], where he is capable of swallowing bubbles for extra breathing time in water. Further 2-Dimension games allow for underwater breathing through the use of air bubbles. In most of the 3-Dimension games, landing in water often results in an instant death and is, alongside bottomless pits, probably the most dangerous obstacle in the newer games. An interview with Yuji Naka states that, Sonic is scared of water because previously Yuji Naka thought that hedgehogs couldn't swim, but then he saw a picture of a hedgehog swimming but he couldn't get out of the water, so the hedgehog needed a tree to get out. This explains that Sonic can go in water, but he thinks he can't get out and that no one would be able to help him, this is the reason he is scared of water.

Sonic also fears Amy when she gets angry, which usually gives him a strong desire to run as far away from her and make it harder to speak to her; this fear increases when he is the one who angers Amy (this is even considering that she can do what Dr. Eggman and his robot army, ancient creatures and entities fail to do). This has happened at least two times, in Sonic Riders and in Sonic and the Black Knight (although for the latter, it wasn't his fault). Though its very likely that Sonic always escapes from Amy since Sonic is faster than Amy and she even admits that she cannot run as fast as Sonic. So when Sonic successfully gets away from Amy, Amy then continues to find Sonic like she usually does. According to Amy's profile in Sonic Channel, it is translated that Sonic acts in a "cringe" when Amy shows her "Iikio", Iikio means "strong power" in Japanese.

There is also reason to believe Sonic reacts terribly to being held captive and may find it mentally and perhaps even physically painful. He seems to act absurd if he doesn't run for a long time, which might mean that he is very much addicted to running, and gets frustrated when something is slow. Like what he told to Elise, ''"If you have time to worry, then run." ''An interview with Yuji Naka states that if Sonic doesn't get to sleep for 8 hours during the night, it would spoil his running.

Sonic also hates to see his friends cry. It has been confirmed that he hates tears and can't bare to see anyone (except Eggman) cry, for he is sensitive about that.

Relationships
This section is for Sonic's relationships in the games continuity only. For relationships specific to versions of the character in alternate continuities, see those versions' respective pages


 * For the SatAM and Archie Comics continuities, see here


 * For the Sonic the Comic continuity, see here


 * For the Sonic X continuity, see here
 * For the Adventures of Sonic the Hedgehog continuity, see here
 * For the Sonic Underground continuity, see hereSonic_and_friends.png, Knuckles and Amy.]]

In the games, Sonic has encountered many people, he has many friends and foes. Sonic is well-known with his brotherly relationship with Tails and his friendly rivalry with Knuckles and Shadow. Sonic's great enemy is Dr. Eggman and sometimes Metal Sonic. Sonic has not currently shown any romantic interest in any females.

Dr. Eggman
"Aw, I'm sorry! I didn't get that memo. I beat you every time!"

- Sonic's response to Eggman when Eggman says that he should had beaten him

Dr. Eggman and Sonic have been enemies even before Sonic met Tails. He always tries to conquer the world and Sonic always thwarts his plans. It is also shown that Sonic can be more frank or taunting towards Eggman in various games, and also shows full confidence that he can spoil his plans no matter what. Sonic, overall, sometimes doesn't take Eggman's plans seriously and will almost always seize the opportunity to tease him. (Such as calling Eggman "Baldy McNosehair" after learning that the Wisps call Eggman "Baldy Nosehair" in Sonic Colors .) It's unknown how they became enemies, but in a scrapped storyline, it was said the were once friends.

Dr. Eggman's real name is Ivo Robotnik, but in Sonic Adventure when Sonic finally encounters him, he teasingly says, "Hey look! A giant talking egg!" Ivo tells him to stop fooling around, then Sonic replies, "Whatever you say, Eggman!" After that, Sonic has been constantly calling him Eggman so much, even his friends started calling him Eggman. Even Ivo calls himself Eggman and doesn't bother when anybody else calls him that anymore. It is stated by Yuji Naka that Sonic uses the nickname "Eggman" affectionately.

Sonic also seems to fall for Eggman's tricks, as shown in Sonic Unleashed, causing him to fall for the doctor's trap and transforming into a Werehog. However, Eggman's plan for turning Sonic into a Werehog was unintentional.

In Sonic's view, the worst creation Eggman has ever made is Metal Sonic, who is really devastating and causes a lot of trouble for Sonic. In Sonic Adventure 2 and Shadow the Hedgehog, Dr. Eggman seems to take Sonic's side to fight Biolizard or Black Doom (mainly because Black Doom is a worse threat than Sonic, as Black Doom wanted to destroy everyone on Earth and the worst that Sonic would do is humilate him).

In Sonic Colors, Sonic often out-smarts Eggman with his jokes and sarcasm. This is shown in the scene when Eggman was constantly trying to pull off puns about his amusement park. When Eggman comes up with a clever pun before the Final Boss Fight, Sonic embarrassed him by saying, "I know you're trying to be clever with this whole 'amusement park pun' thing, but it's just coming off lame! Just say you're gonna destroy us and stop embarrassing yourself!" which angered Eggman, yet he listened to him.

Miles "Tails" Prower
Tails is Sonic's best friend and sidekick. The two have been with each other since Sonic 2. They both have been best friends for so long, they share a brotherly relationship. Sonic and Tails first met in Westside Island, when Tails was being teased by the other children. He saw Sonic running at high speeds, and Tails was impressed by this and thought he was "cool" and went after him. Tails found Sonic's biplane and got so fond of it, he slept under it. Sonic found Tails and they both had a short meeting. When Sonic left, Tails went after him until Sonic stopped. Sonic was impressed by how Tails could keep up and the two became close friends. After their meeting, Sonic and Tails were always there to help each other. Their friendship grew and grew until they had a more brotherly relationship. Tails often invents machines for Sonic and also made him three Extreme Gears. In Sonic Advance 3, they are known as the "Unbreakable Bond" when they team up. In Sonic Rivals 2 it is shown that Sonic trains Tails to learn how to run and fight in their free time. Whenever Sonic has an adventure to explore, he always comes to Tails and asks him to come along, and Tails is always ready to help.

Sonic also seems to care about Tails a lot, like in the opening of Sonic Riders. When Tails was hurt by Storm during a race, he went all the way back to help Tails even though Sonic was leading first place in the race. Tails was also very persistent in making Sonic's Extreme Gear the best Extreme Gear in the world because Wave had insulted Sonic's Blue Star.

Tails also used to depend on Sonic a lot, but later realized that he can't depend on him forever. This was displayed in Sonic Chronicles: The Dark Brotherhood when he says: "I guess without you around I kinda had to grow up a little." Sonic is also an idol and role-model to Tails and he just wants to be as heroic as he is.

In Sonic Unleashed, their bond seems to be closer, like when Sonic was in the form of a Werehog. Tails was the only one in the whole game to recognize him on sight. In Sonic Colors, they are seen together throughout the whole game. It is noticeable that Sonic and Tails seem to be a lot more friendly and act like saving the day is an everyday job, which has not been seen in games for a while. Not to mention, Tails' esteem about Sonic's heroics seems to have dwindled, seeing as Tails cares more about inventing then Sonic's heroic deeds, not even noticing when Sonic does something. When Tails was mind-controlled by Dr. Eggman, Sonic refused to fight Tails and started telling him to get back to his senses. Tails has also embarrassed Sonic when he was talking to a broken robot that can't actually hear him. Sonic told him to forget about the whole thing and it was between him and the robot. In the end of the game, just for Tails' safety, he pushed him to Eggman's elevator so that he doesn't get hurt. Tails was completely unaware that Sonic was ready to push him and unwillingly went down to the planet. (However, in the DS version, Tails willingly leaves.)

Amy Rose
Amy and Sonic first met when Sonic had to save her from Metal Sonic in Sonic CD. After that Amy has been madly in-love with Sonic, and chases him down wherever he goes, however Sonic seems reluctant towards her affection and tries to run away or avoid her most of the times. However, when Amy is in trouble, Sonic is always present to save her and are shown to be good friends. It is very much common in games, whenever Amy comes to Sonic and tries to be romantic with him, Sonic feels uncomfortable and runs away from her.

Sonic seems to have a fear of Amy's anger (in fact it's the only thing so far that can bring Sonic true fear) and runs away with fear when she pulls out her Piko Piko Hammer.

In Sonic Advance 3, before unlocking Amy she comes to Sonic and says, "Sonic! Are you going to ask me out?" Sonic replies no, then Amy says, "Don't you know that we're always meant..." Sonic hesitates and says, "...Together? No! No such thing!" then she pulls out her hammer and says, "Why won't you admit it!?" then Sonic says, "Er... let's not use that hammer, shall we?".

Also in Sonic Adventure 2 when Sonic was in jail and asked Amy to help him get out, she jokingly replies that she'll help him if he'd marry her, to which Sonic replies "No way!". Sonic also seems to find her weird or a pain to him at times such as in Sonic Adventure when Amy wanted to go out with Sonic in Twinkle Park. Out of embarrassment and exasperation he says to himself, "I give up! She's so weird!" or "Ugh, that girl is such a pain!", though he follows after her regardless of complaint.

In Sonic Adventure 2 he is concerned for her when he finds out Eggman has kidnapped her on the Ark. When he's about to be jettisoned into Earth's atmosphere, he tells her to take care of herself.

In Sonic Unleashed, Amy encounters Sonic in his Werehog form. But she doesnt recognize him and runs off to countinue searching for him. Chip then accidently hurts Sonic's feelings by reminding him that people can't recognize him because of his scary new look. Sonic walks away downheaded as Chip tries to apologise and make him feel better. After Sonic saves her from a pack of Dark Gaia creatures who posesses a group of people to have a night party in the streets, he runs away from her. Amy took in a glimpse of him, and was left wondering if that was Sonic. When Amy asks Sonic to go out with her after he saves the world, the player can choose whether Sonic agrees or not.

In Sonic and the Black Knight, it was revealed that the two of them arranged a date prior to the events of the game. After Sonic finishes retelling the exploits of his latest adventure, Amy erroneously believes that it was a lie that he concocted to hide the fact that he had forgotten about their date, and proceeds to chase him with her hammer.

In Sonic Free Riders, Sonic seems to be more annoyed with Amy when she constantly tells him that they have to go out and even tells him that she should take it easy on her in the race. He also tries changing a romantic subject like in the Babylon Story, when Amy runs after him and talks about a date after the Grand Prix, Sonic tries to change the subject by simply saying, "Hi Amy!" suddenly and quickly. In the end of the Team Rose story, Amy forces Sonic to go out with her because she won, but Sonic, not wanting to go, just gives an annoyed look and says "Ugh!". When Amy asks Sonic if she is cute, Sonic tries changing the subject by saying "Ugh... we all had a great time in the Grand Prix, right?"

In Sonic Generations Amy is excited to attend Sonic's birthday. However, Sonic keeps Amy away from getting too close to him because he was talking to Tails by placing his hand over her face. When Classic Sonic rescues Amy, Amy mistakened him for Modern Sonic and questioned on how he looks so young he then breaks the 4th wall with 'strange' look on his face whereas when Modern Sonic saves Amy, Amy tells Sonic that she was afraid that she will never be able to flirt him again, Sonic responds to this by looking back, slapping his palm on his face with an exasperated nod.

Metal Sonic
Sonic and Metal Sonic have a violent rival/enemy relationship. Eggman created Metal Sonic in order to defeat the real Sonic knowing that something as powerful as Sonic would be able to succeed. Since Metal Sonic contains most of Sonic's abilities, they are almost always fighting with each other. Metal Sonic has a strong dislike towards Sonic, always trying to prove that he is better that him in every way and even calls Sonic "My loathsome copy" as well as believing that he is the real Sonic. In Sonic Heroes, when Metal Sonic took control of Eggman's fleet, his intentions were to kill Sonic and then build a robot empire, but Sonic and his allies ended up defeating him, and afterwards Metal Sonic asked Sonic why he couldn't beat him and shut down. Also in this game, Metal Sonic's real emotions towards Sonic were released.

Metal Sonic's hatred for Sonic went on after that, even after Eggman restored him to his robotic slave. He later broke free from Dr. Eggman's control once again in Sonic Free Riders in order to face Sonic, this time in Extreme Gear, but he was defeated once more in a one-on-one race.

Knuckles the Echidna
Ever since Knuckles' introduction, there was recurring and unfinished battle between Sonic and Knuckles. Because of their differences and morals, the two are constantly getting into a crossroads, which then devolve into outright fisticuffs. However, they finish the battle tied, or something serves to interrupt the battle before its end. The battle has appeared in the games. It occurs in many games featuring Knuckles since his debut in Sonic 3. With Sonic's speed paralleling Knuckles' strength in every way, their fights are always climactic.

It should also be noted that in various games, Sonic teases Knuckles whenever Knuckles falls for Eggman's tricks by making a pun out of his name; "Knuckle-head". In Sonic and the Black Knight, Sonic says to Gawain, "Hey! You look like that Knuckle-head I know!" even without having Gawain making a mistake and when Gawain accused him of wanting to steal the dragon's treasure, he remarked "Ugh, you SOUND just like that Knuckle-head too!", noticing the similarity between Knuckles and Gawain in personality. In Sonic Rivals 2 Sonic teases Knuckles when he sees Knuckles and Rouge together by saying, "Well look who it is... Knuckles and Rouge! You two on a date or something?" Knuckles tells him to stop fooling around and get back to what was important.

The rivalry has all but disappeared in some continuities, and in others, it is a sort of game between the two, actually serving as the plot for the game Sonic Rivals 2, when Knuckles tells Sonic that he needs to find Eggman, Sonic taunts him by saying that he'll beat Knuckles to Eggman, causing them to fight.

Overall, they are great friends and make a great teamwork, next to Tails, Knuckles is also Sonic's best friend.

In the DS version of Sonic Colors when Sonic heard that Rocket Wisps are easy to anger and easy to be happy, Sonic compares them to Knuckles. Later in the game, Sonic meets Knuckles at Starlight Carnival. Sonic and Knuckles still retain their rivalry but do not really argue. Instead, Sonic tries consoling Knuckles in getting angry when he was not accepting on getting tricked by Eggman, Knuckles keeps on yelling that he did not get tricked Sonic replies, "Alright! Alright! You didn't!". Tails also comment that Sonic and Knuckles are "funny" together. When Rouge tells Knuckles that the invitation was actually written by her, Knuckles becomes restless realizing that he did get tricked. Sonic tries cooling Knuckles down by saying that at least Eggman didn't trick him, but Tails doubted that would make Knuckles feel better

Shadow the Hedgehog
Shadow is the dark doppelgänger of Sonic. They look alike (to the extent that many characters got them confused in Sonic Adventure 2), they are both super fast, and they can both use Chaos Control. Because of these similarities, as well as their moral differences and sense of pride, they have become arch-rivals that try to defeat each other constantly.

It was the result of Shadow's actions that sent Sonic to jail, even when Sonic wasn't guilty, in Sonic Adventure 2. In the end, however, Sonic realizes that Shadow was on Earth for a purpose, to fulfill his promise to Maria, that is the reason why Sonic realized that Shadow is actually a great hero. After defeating the Biolizard and Shadow's apparent "death", Sonic recalls that Shadow is a brave and loyal hedgehog and he'll never forget a great person like him.

Out of all the rivals and opponents Sonic faces, Shadow is the one whom he has the most fun with and the most time with struggling. Shown in all the clashes between the two, they are nearly equal or as strong as the other with both sides proving to be neither lacking in any category that seperates them from skill in their respective prowess. Later on it is shown that Sonic is getting faster and more honed than Shadow, and Shadow is getting more destructive and powerful than Sonic, both having different skill sets from each game while retaining their inital basic attacks and speed. They have a strong rivalry based on a need to showcase their growth and improvement for each and every encounter they have.

In Sonic Generations they still share a fierce competition, but this time Shadow displays a slighty more friendly interest in Sonic. In the beginning Shadow is not present at the begining of Sonic's birthday party. However, they do encounter each other in the White Space where Shadow is determined to beat Sonic; so much in fact that he does not care where he has been brought to. He also appears at Classic and Modern Sonic's final fight with the Time Eater, where he is encouraging the Sonics to win, which is something Shadow rarely does. After the battle and returning to their own time, Shadow decides to stay at Sonic's birthday party, although he remains in the background,

Blaze the Cat
Sonic and Blaze first met when she was searching for the Sol Emeralds in Sonic's world in Sonic Rush. At first, Blaze did not care who Sonic was as Cream and a few others told her to seek his help, but she claims that she does not need anyone to help her. Sonic was quite interested in Blaze to the point where he decided to find and help her. Though Sonic only intended to help her, Blaze started to attack him thinking he was her enemy.

Their battle ended in a draw and Blaze realizes that Sonic is not her enemy and the two became friends and combat partners. Later, when Dr. Eggman and Eggman Nega team up, Blaze starts to lose faith in herself, but Sonic cheers her up, as soon as she regains faith and learns the power of true friendship she was able to use the power of the Sol Emeralds and become Burning Blaze while Sonic becomes Super Sonic and they team up to defeat them. After their battle, they say their goodbyes Blaze thanks Sonic and the two made a promise that they will meet again and the two shook hands as they were separated. In the ending of Sonic Rush, Blaze remembers Sonic's words about her flames, not being a curse, but an inherited gift and about her learning the power of the Sol Emeralds, then he says "And Blaze now you have that power! You know what I mean, right?", Blaze then smiles and once again says that they will meet again.

In their next meeting, Sonic ends up in Blaze's dimension, along with Tails, where they work together as allies to stop the Doctors' plans. After defeating them, Blaze tells Sonic that it is possible that the Emeralds brought him to her world as if it was destiny. Sonic, confused for a second, smiled and said "Who knows?", Blaze then brings out her hand to give Sonic the same handshake they did before and Sonic accepts, positive that will meet again and their friendship grows.

Sonic seems to be very amazed by Blaze, seeing as how she is one of the few people who is able to equally match him and possibly have the potential to defeat him in direct combat. Blaze, in turn, is very impressed with Sonic's skills and once said that she "bows before his skills". Blaze also seems to rely on Sonic the most and has a certain respect him to the point where she considers him as her most trusted ally and friend.

In Sonic Generations Blaze attends Sonic's birthday party. This possibly proves that she cares so much about Sonic that she had apparently left her duties as the princess of her dimension and guardian of the Sol Emeralds simply to celebrate his birthday. When Sonic saves her from being frozen by the Time Eater she says that she dislikes relying on others, but is still very grateful for him saving her and believes that Sonic can defeat the monster.

Silver the Hedgehog
Sonic and Silver first met during the events of Sonic the Hedgehog (2006)). The two were enemies at first because Silver had travelled though time and was intending to kill Sonic believing that he was responsible for destroying his time by releasing Iblis onto the world and was bent on saving the future. But Silver befriended Sonic when he discovered that Sonic was not the Iblis trigger and that Mephiles the Dark had lied to him. The two worked together to save Princess Elise and when Sonic was killed by Mephiles, Silver realized that they could save Sonic with the power of the Chaos Emeralds. Afterwards Silver teamed up with Sonic and Shadow to defeat Solaris. But since the events of the game were erased from history, Sonic and Silver never met. They don't actually meet until Sonic Rivals where Silver has travelled to the past to bring Eggman Nega back to the future, but Silver seems to be more competitive to Sonic as they raced each other see who would get to Eggman Nega first but later they teamed up with each other at the end to defeat Eggman Nega and also in Sonic Rivals 2 to defeat the Ifrit. It appears that Sonic and Silver don't remember each other from their past adventure since the events of Sonic the Hedgehog (2006) were erased.

Silver seems to have a bit of a disliking towards Sonic moslty because he thinks that he is cheeky and foolish, much the same how Shadow thinks of Sonic at times. Silver's attitude tends to annoy Sonic at times as well as seen in Sonic Rivals when he says "Yo Silver, you've got an attitude". But they will work together and lay aside their differences whenever the time is right. An example is in Sonic Colors after Silver challenges Sonic to a mission, he asks if Sonic if he needs any help. Silver is one of the characters that Sonic would like to challenge as seen in Sonic Rivals, when Silver said to him that he had to get to Eggman Nega first before Sonic did, Sonic said "Okay Silver, bring it on, I like a challenge!". Their relationship is very similar to Sonic and Knuckles.

Classic Sonic
Sonic meets his younger Classic self from the Genesis era after being thrusted back in time, while celebrating his birthday, in Sonic Generations. At first Sonic could not recognize his Classic form by just calling him "another Sonic" and by mistaking him for his reflection when the glass was just glass and not just a mirror. Sonic teams up with himself and travels through time (again) to save the world. They seem to have great teamwork and share the same gestures simultaneously in every scenes, this is due to them being the same person.

To Modern Sonic, Classic Sonic is sort of like a younger brother to him, someone who is hyped up on simply running and rolling around just simply enjoying life to the fullest. He looks forward to seeing him progress, seeing as he has learned and experienced these things before.

To Classic Sonic, Modern Sonic is somewhat like a cool older brother and a role model to how he may become. He's very eager to learn all of the new tricks that Modern Sonic has developed over the years, like in the end of Sonic Generations where he attempts to do a Sonic Boost/Homing Attack. In the 3DS version of Sonic Generations, Sonic called his past self partner.

Friends/Allies

 * Miles "Tails" Prower (best friend, close as brothers)
 * Knuckles the Echidna (best friend and rival)
 * Amy Rose (self-proclaimed girlfriend)
 * Shadow the Hedgehog (friend and arch rival)
 * Blaze the Cat (close friend and partner in combat)
 * Rouge the Bat
 * Vector the Crocodile
 * Espio the Chameleon
 * Charmy Bee
 * Silver the Hedgehog (ally and friendly rival)
 * Cream the Rabbit (good friend)
 * Cheese the Chao
 * Vanilla the Rabbit
 * Jet the Hawk (rival at speed)
 * Wave the Swallow
 * Storm the Albatross
 * Big the Cat
 * E-123 Omega

Rivals

 * Shadow the Hedgehog (arch rival)
 * Knuckles the Echidna (old rival)
 * Silver the Hedgehog
 * Jet the Hawk
 * Metal Sonic
 * Mario (friendly rival)
 * Blaze the Cat (formerly)

Enemies

 * Doctor Eggman
 * Metal Sonic
 * Dr. Eggman Nega

Trivia

 * There is a hedgehog genome named Sonic hedgehog.
 * In 1993, Sonic was the first video game character to appear in the Macy's Thanksgiving Day Parade. (The second was Pikachu from the Pokémon franchise in 2001.) Sonic reappeared in the Parade in 2011 as the lead of the parade, to commemorate his 20th Anniversary.
 * If left alone too long in the first Sonic game, Sonic will become impatient, and tap his foot on the ground until the player continues.
 * In Sonic CD, after standing for three minutes, he will say "I'm outta here" and jump off the screen, and the "GAME OVER" screen will appear.
 * Sonic Adventure 2, Sonic Riders, Sonic Riders: Zero Gravity, Sonic Free Riders, and Sonic Unleashed (while in Werehog-Form) are the only games where Sonic is wearing different shoes.
 * Sonic's first appearance in games wasn't in Sonic the Hedgehog, but in Rad Mobile.
 * In all classic Sonic games, as well as Sonic Adventure, Sonic Adventure 2, Sonic Advance 1, 2 and 3 when Sonic closes his eyes, his eyelids are the same color as his arms and muzzle, but later, they were changed blue. Currently, they are still blue. However, in one of the commercials, his eyelids weren't blue. And in the commercial of the game in Japan, he had no eyelids. He does blink twice in the commercial, but he still has his eyes open when he blinks. This was referenced in Sonic Generations, where as Modern Sonic has blue eyelids, while Classic Sonic has flesh-colored eyelids.
 * Sonic has made a playable cameo appearance in the Christmas NiGHTS bonus event Sonic the Hedgehog into Dreams. This was also Sonic's first true 3D appearance.
 * Sonic's favorite food is Chili dogs.
 * According to an interview in Sonic Central, Sonic does not know the whereabouts of Mighty the Armadillo, Ray the Flying Squirrel, Nack the Weasel, Bark the Polar Bear and Bean the Dynamite.
 * In Sonic Rush, if you tap Sonic with the stylus during gameplay, he would clap, jump back and forth, then he'll continuously swing his arm clockwise as if he is exercising.
 * Originally Sonic was supposed to have visible fangs in the Japanese artwork, but they were removed when he was given a more Americanized design for the US artwork in order to "soften him up" a bit. Although he does have fangs they are only visible when he opens his mouth (this can mostly be seen in Dreamcast titles like Sonic Adventure and Sonic Shuffle, but stopped being as noticeable after Sonic Adventure 2). Before, his fangs were supposed to be visible even when the mouth is closed.
 * On some drawings such as official artwork for SegaWorld Sydney and a few animation cels, his arms are mistakenly colored blue.
 * Sonic has tied for 10th best selling series with Nintendo's The Legend of Zelda.
 * In the game "Little Big Planet", one can customize the sackboy into the Sonic the Hedgehog look, along with other costumes such as Knuckles, Tails, Eggman and Sonic the Werehog.
 * Sonic's age has always been a tricky one to pinpoint. a mistranslation in the original Japanese﻿ manual states that he was 10 years old. According to the Sonic Technical Files, it says he is 18, "but it's kinda hard to tell. Once Sonic Jam was released, it looked like it was solidified at 16, but Sonic Channel had finalized it as 15. As of Sonic Generations he and the rest of the cast have been elevated by one year.
 * In the Japanese versions of the games, Sonic has shown that he knows the most amount of English out of all other characters, as he is the only one who uses English many times in the games. This may be due to the fact that the English language is considered "cool" in Japan and therefore makes sense to have the "coolest" character have many English lines, as well as his Japanese voice actor wanting him to.
 * Sonic is the first character to utilize the Chaos Emeralds by transforming into Super Sonic in Sonic the Hedgehog 2.
 * In the 2011 Guinness World Records Gamers Edition, Sonic placed 10th in the "Top 50 Video Game Characters of all time." His rival, Mario, placed first, and Shadow placed 25th.
 * Any time Sonic is in a band he is the guitar player.
 * It could be possible that Sonic can move faster than the speed of light. It's implied in the DS version of Sonic Colors, after Sonic gets an S on Omega's mission. When Omega collected data from Sonic, he said "At this rate, light speed will be exceeded." Then Sonic told him that light speed was slow time and not a challenge. However, this may just have been just a joke to mess with Omega.
 * Sonic has been chased by something numerous times in 3D games (A whale in Sonic Adventure, a G.U.N. truck in Sonic Adventure 2, three giant spiky wheels and a giant alligator in Sonic Heroes, a fire tornado and another whale in Sonic the Hedgehog (2006), a group of triceratops in Sonic and the Secret Rings, a black hole in Wii version of Sonic Colors, and a helicopter and a truck in Sonic Generations).
 * He is notorious for breaking the fourth wall.
 * In the game Project Diva Extend, Hatsune Miku can dress up as Sonic.
 * Apparently, Sonic and his friends are able to breathe in space as seen in several games and Sonic X, though cannot breathe underwater without the support of bubbles.
 * All of the cars thet Sonic has driven in have been sports convertables, similar to how Amy has only driven old fashioned ones.
 * Sonic doesn't mind being considered a villan if it means doing the right thing, as stated in Sonic and the Black Knight.
 * Severl cutscenes in the less lighthearted games have showen that Sonic might have trouble when dealing with more serious emotions such as love this is a sterotypical trait of the character type Soinc is based off of.

Memorable Quotes

 * "I'm Sonic. Sonic the Hedgehog." - Sonic introducing himself.
 * "Tails, long time no see!" - Sonic greeting Tails in a few games.
 * "I'm outta here!" - Sonic when the player waits for too long in Sonic CD.
 * "Aw, yeah! This is happenin'!" - Sonic enjoying a run on building rooftops in his intro of Sonic Adventure.
 * "It won't change how he feels inside, will it? His heart will still remain in turmoil and his anger just won't vanish!" - Sonic claiming that sealing Chaos in the Master Emerald will not change anything, in Sonic Adventure.
 * "Hey, I'll play with you some other time!" - Sonic in Sonic Adventure after defeating a boss.
 * "Say something! You fake hedgehog!" - To Shadow when first encountering him Sonic Adventure 2.
 * "Too easy. Piece of cake!" - Sonic getting a B Rank in Sonic Adventure 2 and winning a match in Super Smash Bros. Brawl.
 * "Let's head back to the planet that's as cool and blue as me!" - After defeating the Finalhazard and talking with Amy in Sonic Adventure 2.
 * "Game over, Shadow" - Sonic to Shadow in Sonic Adventure 2
 * "Let's blast through with Sonic speed!" - Selecting Team Sonic in Sonic Heroes.
 * "Time to crack that Eggman wide open... Yeah, let's party." - Sonic in the Team Sonic intro from Sonic Heroes.
 * "Shoot! Not my day..." - Sonic getting an E-Rank in Sonic Heroes or getting a 1-Star rank in Sonic and the Black Knight.
 * "Ready anytime!" - When Sonic gets a Team Blast for Team Sonic in Sonic Heroes.
 * "Alright. Let's get ready to do this. We'll show that creep the real super power of teamwork!" - Sonic and friends about to confront Metal Madness in Sonic Heroes.
 * "Anytime you want a rematch, just let me know! I'll be waiting!" - Sonic challenging Metal Sonic to a future match in Sonic Heroes, later to be done in Sonic Free Riders.
 * "Let's do it!" - Sonic in the beginning of the levels in Sonic Rush and Sonic Rush Adventure.
 * "You need to be true to yourself!" - Sonic talking to Blaze in Sonic Rush.
 * "Looks like the party's getting started! Time to rock and roll!" - Sonic about to go to a stage with Shadow in Shadow the Hedgehog.
 * "You up for this Shadow?" - Sonic asking if Shadow's up to fight a massive army of Black Arms when they were going up to the Space Colony Ark in Shadow the Hedgehog.
 * "Don't you remember Shadow? We raced here once." - Sonic asking Shadow if he remembers their race from Sonic Adventure 2 in Shadow the Hedgehog.
 * "Nothing starts until you take action. If you've got time to worry, run!" - Sonic talking to Elise in Sonic '06.
 * "Aren't you worried?" - Sonic rescuing Elise for the final time in Sonic '06.
 * "You're too slow!" - A very famous quote when taunting in Super Smash Bros. Brawl.
 * "Sonic's the name, speed's my game!" - After winning a match in Super Smash Bros. Brawl.
 * "Come on, step it up!" - Sonic taunting in Super Smash Bros. Brawl.
 * "Hey, we should do this again sometime." - Sonic winning a match in Super Smash Bros. Brawl.
 * "Too easy, piece of cake!" - Sonic whips out a Chaos Emerald after winning a match in Super Smash Bros. Brawl.
 * "Finally! Something interesting!" - Sonic in the teaser trailer for Sonic and the Secret Rings.
 * "And enough of that 'rat' stuff! Seriously! I'm a hedgehog! HEDGE-HOG!" - After the Erazor Djinn calls Sonic a rat in Sonic and the Secret Rings.
 * "I told you, I'm not a rat! I'm a hedgehog!" - Sonic when Erazor "fufills" Sonic's final wish of trapping Erazor forever in his lamp in Sonic and the Secret Rings.
 * "Yeah, this is the real me. Pretty cool huh?" - Sonic telling Chip that this is what he usually looks like in Sonic Unleashed.
 * "Yo, Eggman. Thanks for that little skydiving adventure the other day!" - Sonic after saving the people of the village in Mazuri.
 * "Not a bad toy, but play time's over pal!" - Sonic after defeating the Egg Beetle of the daytime bosses in Sonic Unleashed.
 * "Do I need a reason to want to help out a friend?" - Sonic after discovering that Chip is actually Light Gaia, who believes that defeating Dark Gaia is not Sonic's responsibility.
 * "Time for the big finale!" - Sonic in the final battle against Dark Gaia in Sonic Unleashed.
 * "Eh. Can't win em all..." - Sonic when getting a C rank in Sonic Unleashed.
 * "Yeah, I'm good!" - Sonic after getting an A rank in Sonic Unleashed.
 * "Beautiful!" - When Sonic gets an S rank in Sonic Unleashed.
 * "Hey! Hold up a minute. Girls hate guys who rush them, Jet." - Sonic coming to Amy's aid after Jet accuses her of stealing an Ark of the Cosmos in Sonic Riders: Zero Gravity.
 * "I'm Sonic the Hedgehog. I have no master, except the wind that blows free." - Sonic introducing himself to Sir Percival in Sonic and the Black Knight.
 * "Let's just say that whim is my other master." - Sonic after saving Sir Percival after their fight in Sonic and the Black Knight.
 * "Just one more question before we settle this. Why'd you do it? Weren't we trying to save this kingdom from the underworld?" - Sonic confronting Merlina when he first enters the barrier in Sonic and the Black Knight.
 * "A knight... never... flees his foe... right?" - Sonic restating Caliburn's words to the knights of the round table when he refuses to run away from Merlina during their fight in Sonic and the Black Knight.
 * "It was... never about chivalry for me... I just gotta do what I gotta do, that's all!" - Sonic when badly beaten by the Dark Queen in Sonic and the Black Knight.
 * "Faster than the speed of sound!" - Sonic before starting an event in Mario and Sonic at the Olympic Winter Games.
 * "Wait, we're going up against them? Seriously?" - Sonic after he found out he had to go up against Team Rose in Sonic Free Riders.
 * "Because Eggman plus secretly built amusement park equals evil plot for us to foil." - Sonic talking to Tails at the beginning of the story in Sonic Colors.
 * "I did a little shopping, grabbed a bite to eat, and trashed a giant killer robot." - When Tails was wondering where Sonic was in Sonic Colors.
 * "Hey Tails! You missed the BBBE!" - Sonic telling Tails that he missed the "Best Boss Beating Ever" in Sonic Colors.
 * "Experience has taught me to investigate anything that glows." - Sonic going to investigate one of Eggman's generators in Sonic Colors.
 * "BALDY NOSEHAIR!? That is the best thing I've heard all day! I gotta remember that one!" - Sonic laughing when Tails told him that the Wisps call Eggman "Baldy Nosehair" in Sonic Colors.
 * "No copyright law in the universe is going to stop me!" - Sonic in Sonic Colors before fighting the boss on Planet Wisp.
 * "A hedgehog's gotta do what a hedgehog's gotta do." - Sonic tells Tails he did what he had to in order to defeat Eggman and outrun the black hole that enveloped the theme park in Sonic Colors.
 * "like it? I love it!" - After Sonic discovers the surprise birthday party.
 * "Hey! Not cool!" - To the Time Eater at their first meeting in Sonic Generations.
 * "Another Sonic?! What!?! Wait a second!" - When Modern Sonic meets his Classic self before the boss fight with the Death Egg Robot.
 * "An adventure's no fun if it's too easy" - To Classic Tails when Tails says they have their work cut out for them.
 * "Destroy me? You and what mustache? I beat you all the time by myself, and now there's two of me!" - to both Dr. Eggman and Dr. Robotnik before the 1st half of the boss fight with the Time Eater, he's referring to the fact there's both Modern and Classic Sonic.
 * "Ha! still warm, time travel" - When Sonic catch's a chillie dog after defeating the final boss. 
 * "It was great teaming up with you. Hope you learned a few tricks that'll help you out in the future. I mean the past. You know what I mean!" - Sonic to his Classic self after they've restored the time-space rift in Sonic Generations.
 * "Hey Sonic! Enjoy your future. It's going to be great!" - Sonic's farewell to his Classic self when he is going to return to his original timeline, at the ending of Sonic Generations.

Solo Themes

 * In Sonic CD, Sonic's theme is "Sonic Boom." In the Japanese version, his theme is "Sonic - You Can Do Anything."
 * In Sonic Adventure, Sonic's theme is "It Doesn't Matter."
 * Also, in Sonic Adventure 2, the City Escape stage has lyrics to the music, which refer to Sonic in the line "Rollin' around at the speed of sound".
 * In Sonic Adventure 2, Sonic's theme is a a faster-paced, alternative rock remix of "It Doesn't Matter."
 * In Sonic the Hedgehog (2006) the main theme "His World" is possibly a Sonic theme because the Zebrahead version has lyrics like "and straps on his shoes" a reference to Sonic because of his iconic shoes and "cause' he's the best there ever was, i betcha' heard the news" because he is often referred to as a savior to mankind and he is known by many in his world.
 * In Sonic and the Black Knight the main theme "Knight of the Wind" is probably referring to Sonic, for Caliburn eventually calls him so.
 * In Sonic Unleashed, Sonic's theme is "Endless Possibility," which describes life from his point of view.
 * In Sonic Colors, his theme is "Reach For The Stars" describing from his point of view on his new adventure.

Shared Themes

 * In Sonic Adventure 2, he shares the theme "Live and Learn" with Shadow.
 * In Sonic Heroes, Team Sonic's theme is "We Can," and refers to Sonic in the lines "Look out down below, Sonic is on the go" and "Sonic's in the lead, giving us greater speed!"
 * In Sonic Riders, Sonic's team theme, shared with Tails and Knuckles, is an instrumental called "High Flying Groove."
 * In Sonic Riders: Zero Gravity, Team Sonic's theme song is "Un-Gravitify."
 * In Sonic Free Riders, Free could have some connection with both Sonic and his Extreme Gear rival Jet.

Gallery
For a full gallery of images of Sonic, including sprites and screenshots, see Sonic the Hedgehog (character)/Artwork Gallery.