Sonic the Hedgehog series

The Sonic the Hedgehog series is a franchise of video games released by Sega starring their mascot character, Sonic the Hedgehog. The series began in 1991 with the release of Sonic the Hedgehog on the Sega Mega Drive/Genesis. An 8-bit version of the game was also released for the Master System and Game Gear formats. Sonic was responsible for turning Sega into a leading video game company early in the 16-bit era, and his first game soon replaced Altered Beast as the default pack-in game for the Genesis in North America and Europe.

As of 2013, the franchise had sold more than 140 million units, making the series the 5th best-selling video game franchise of all time.

Games in the series are developed by Sonic Team, with the exception of some spin-offs that were independently developed by Sega of America. The main programmer for the first game was Yuji Naka, who would later become head of the Sonic Team division, and the game planner was Hirokazu Yasuhara but stopped producing games for the franchise. The music of the first two Sonic the Hedgehog games on the Mega Drive/Genesis were composed by Masato Nakamura of the Japanese band Dreams Come True.

Yuji Naka, Hirokazu Yasuhara and Naoto Oshima stopped producing games for Sonic. Yuji Naka became the head of his own franchise, Prope, Oshima joined the company Artoon, and Yasuhara moved to Namco a gaming company. As of current, Takashi Iizuka is the head of Sonic Team and has been involved in several current Sonic games. Most of his involvement was/is in Sonic Colors and Sonic Generations, he took very little involvement in the Storybook series. Currently, most of the music is done by SEGA Sound Team or Crush 40.

Overview
Nearly all games in the series feature a teenage hedgehog named Sonic as the central player character and protagonist. The games feature Sonic's attempts to save his planet from various threats, primarily the evil genius Dr. Ivo Robotnik, presently referred to as Dr. Eggman. The main antagonist throughout the series, Robotnik's aim is to rule the planet and establish the Eggman Empire; and to achieve this, he usually attempts to eliminate Sonic and acquire the powerful Chaos Emeralds.

History
Most two-dimensional Sonic titles are platform games viewed from a side-on perspective. Their controls are fairly basic and do not deviate much from the genre standard; the selling point of the series is the incredible speed of the playable characters, who usually have the ability to run uphill, walls, and even ceilings. Roller coaster-like loops and corkscrews are also common in Sonic games, as are giant pinball machines with flippers and bumpers which knock Sonic around like a ball. The stages are also similar to roller coasters in that many sequences involve Sonic being thrown along preset paths with little input from the player, which has led to criticism that the player can complete a Sonic game merely by holding the pad in one direction. However, the games also feature numerous sections involving precise jumping between platforms and avoiding of hazards, although these sections do not require "pixel-perfect" judgment and are perhaps more lenient than most platform games of the era. Three-dimensional Sonic titles feature more free movement and controls are slightly more advanced.

The Sega Technical Institute tried to develop a "true" Sonic game for the Saturn called Sonic X-treme. This game was intended to compete with Nintendo's Super Mario 64. However, due to time constraints and issues between STI and the Japanese division of Sega and Sonic Team, the project was canceled in the last months of 1996.

Sonic 3D Blast, an isometric, pseudo-3D ("2.5D") game, was released for the Mega Drive in 1996. Sega Saturn and Windows PC conversions followed to cover the hole of the cancellation of Sonic X-treme. They had enhanced graphics and a different sound track, composed by Richard Jacques. Sonic 3D Blast was developed by Traveler's Tales, although Sonic Team worked on the Special Stages in the Saturn/PC version.

In 1997, a compilation entitled Sonic Jam was released for the Saturn. In addition to containing Sonic the Hedgehog, Sonic the Hedgehog 2, Sonic the Hedgehog 3 and Sonic & Knuckles, it also included a "Sonic World" mode. This allowed the player to control Sonic in a small 3D world similar to the Green Hill Zone from the original game; it contained no enemies and was mainly a means of accessing the disc's multimedia features such as BGM's, illustrations and even commercials. Although Sonic R was the first 3D Sonic game, the full leap into 3D platforming was made with Sonic Adventure, a launch title for the Sega Dreamcast console. On 7 June 2001 in North America (23 June in Japan and Europe; the 10th anniversary of the US release of Sonic the Hedgehog), Sonic Adventure 2 was launched. Both of the Adventure titles were later ported to the Nintendo GameCube (under the titles of Sonic Adventure DX and Sonic Adventure 2 Battle) when Sega dropped out of the hardware market. DX was also ported to Windows PCs.

The first Sonic game to release simultaneously on multiple consoles, Sonic Heroes, was released on the GameCube, PlayStation 2 and Xbox in December 2003 in Japan, with American and European releases following soon after and a PC version during the following November. The platforming was largely similar to that of the Adventure titles, although the player now controlled the lead character of a team of three themed characters, with the other two following closely behind. The player could switch to a new leader at any time, in order to make use of each character's special skills. It sold well, but opinions among both reviewers and fans of the Sonic series were mixed.

Shadow the Hedgehog also had mixed views. Released in the US in November 2005, it received mixed reviews from reviewers such as X-Play, for instance, who had given it a 1 out of 5, making it the lowest-scoring Sonic game reviewed on the show. Other game sites such as IGN and GameSpot similarly panned the game. One of the greatest controversies revolving around this game is the gun play; some fans insisted that Shadow was the self-proclaimed "Ultimate Life-Form" and did not need a weapon. Nintendo Power and Gametrailers, however, both rated it above 8 out of 10, praising the replay value. Two other controversies were the over-use of minor profanity and the fact that Sega had decided to switch to the 4Kids voice actors from the English version of Sonic X.

A highly faithful two-part port of Sonic the Hedgehog made for mobile phones has been a huge hit in Europe, introducing the game to a new generation of preteen gamers, with respected handheld specialist Pocket Gamer awarding Sonic the Hedgehog Part Two a 9 out of 10 review score.

Other gameplay styles
A few Sonic games focus on gameplay styles other than the standard platforming. The first of these was Sonic the Hedgehog Spinball (released on the Mega Drive in 1993 and on the Master System and Game Gear in 1994). The concept of Sonic bouncing around as the ball in a giant pinball table had been used in both Sonic the Hedgehog and Sonic the Hedgehog 2; Sonic the Hedgehog Spinball was designed around that premise.

Several racing games starring Sonic characters have been developed. In Sonic Drift and Sonic Drift 2, characters drive go-karts (kart circuits were later included in the two Sonic Adventure games). In Sonic R (1998), most characters ran on foot (with Eggman riding his Eggmobile and Amy driving a car), while in the Sonic Riders series (2006), they race on hoverboards.

Sonic Shuffle was a Mario Party-style virtual board game/party game for the Sega Dreamcast.

Edutainment video games starring Sonic and Tails have also been released, such as Sonic the Hedgehog's Gameworld and Tails and the Music Maker for the Sega Pico, and the PC title Sonic's Schoolhouse.

A fighting game named Sonic the Fighters existed as an arcade game, and later a fighting/platform game hybrid called Sonic Battle was released for the Game Boy Advance.

In 1993, Dr. Robotnik's Mean Bean Machine was released for the Sega Mega Drive. The game was a clone the Japanese puzzle game Puyo Puyo. This game was also ported to the Game Gear.

Sonic Chronicles: The Dark Brotherhood brought Sonic into the world of RPGs for the first time, mixing turn-based combat and story telling with traditional Sonic elements.

Giant Rings
Whereas most Rings were small and easily collectible, certain Rings appeared that were much larger. The so-called "Giant Rings" were hidden in the stages and designed to be jumped through, which would transport the character to a Special Stage, where the character could collect one of the Chaos Emeralds or, in certain circumstances, Super Emeralds. They were used for this purpose in the games Sonic the Hedgehog, Sonic the Hedgehog CD and Sonic the Hedgehog 3 & Knuckles. Sonic the Hedgehog 2 used Star Posts instead. In Sonic the Hedgehog 3, if all the Emeralds had already been found, these rings could be collected for fifty rings each, allowing the characters to easily tap into the power of the Chaos Emeralds (usually becoming Super, or Hyper in Sonic the Hedgehog 3 & Knuckles if the player has collected all the Super Emeralds as well). In most of the newer games since Sonic Adventure 2, these giant rings have taken the place of the old signposts as the end level marker and touching it would end the level.

Shuttle Loops
Shuttle Loops are simply lood-de-loops that the player runs through as part of the main path during a stage.

Chaos Emeralds


The Chaos Emeralds are seven emeralds with mystical powers which are a recurring feature of Sonic games. They are the basic of most of the games' plots and the player is frequently required to collect them all in order to fully defeat Eggman and achieve the games' "good endings", Super Forms, or both. The method used to acquire the Emeralds differs between titles in the series. Most early games require the player to find them in Special Stages. In some games, such as Sonic R and the 8-bit versions of Sonic the Hedgehog and Sonic the Hedgehog 2, they can be found in hidden locations within the main levels. In most later games, the Chaos Emeralds are found by the characters throughout the games' story modes and do not need to be "found" by the player.

A counterpart to the Chaos Emeralds, known as the Sol Emeralds, appear in the Sonic Rush series.

Master Emerald
The Master Emerald resides in a shrine on Angel Island and is guarded by Knuckles the Echidna; it contains an infinite amount of power, much greater than the 7 Chaos Emeralds, and is used to keep the Angel Island afloat in the sky. The Emerald also has the power to fully control everything that the Chaos Emeralds do, including the ability to negate the energy of the Chaos Emeralds, as seen in Sonic Adventure and Sonic Adventure 2, or empower them, as seen in Sonic the Hedgehog 3 & Knuckles. The Master Emerald can also be used to power mechanical devices, and has been coveted by Dr. Robotnik since his discovery of it. During Knuckles' final boss fight in Sonic the Hedgehog 3 &amp; Knuckles, Mecha Sonic powers up using the Master Emerald into a Super State. In earlier materials, the Master Emerald was sometimes called an eighth Chaos Emerald, but this association has been lessened in later games, making it a separate but related entity.

Special Stages
Usually, a Chaos Emerald may be earned in a Special Stage or Special Zone. Special Stages usually take place in surreal environments and features alternate gameplay mechanics to the standard platforming of the main levels: the 16-bit Sonic the Hedgehog  consisted of a giant rotating maze (which many considered a major technical achievement); Sonic the Hedgehog 2, Sonic 3D Blast, Sonic Heroes and Sonic Rush featured "in your face" segments with the hedgehog running along a long tunnel, with a variant of this used for Knuckles' Chaotix, Sonic Advance, and Sonic Advance 3; 3D "collect items" levels, as in Sonic the Hedgehog 3 &amp; Knuckles, which used the same perspective but had Sonic collecting all the blue-colored orbs on the surface of a giant sphere and a different version, the 3D ring-collecting Special Stage, used in Sonic Advance 2. Sonic Chaos (Sonic & Tails in Japan) utilized a variety of gimmicks for its levels.

Some Sonic titles include Special Stages, but not as a means of collecting Chaos Emeralds. As the Emeralds of the 8-bit version of Sonic the Hedgehog were hidden in the main stages, the game's spring-filled Special Stages were merely used as a means of adding variety, and for a player to increase their score. Similarly, Sonic the Hedgehog 3 &amp; Knuckles, in addition to their main Special Stages, featured entirely optional bonus stages, one of which combined the rotating maze of the 16-bit Sonic the Hedgehog with the pinball gambling of Sonic the Hedgehog 2 and Sonic Heroes had an alternate Special Stage for earning lots of 1-Ups, very much like the one in which Chaos Emeralds are collected, but with the objective being to get to the Goal Ring before time ran out, rather than catching up to the Chaos Emerald at the end of the tunnel.

Just as the design of the Special Stages has changed, so has the means of accessing them. In Sonic the Hedgehog 3 & Knuckles, giant rings were hidden in levels to take the player to the Stages, but most other titles involve the collection of a certain number of rings, usually 50. In both the 8- and 16-bit versions of Sonic the Hedgehog, they were reached by finishing a level with more than 50 rings; the player would then have to jump inside the giant ring that would appear just after the goal post. In the 16-bit Sonic the Hedgehog 2, reaching a Star Post when they held this number would create a warp of stars which would take a player to the Special Stage when jumped through. Sonic 3D Blast required the player to deliver rings to Knuckles and Tails, who could be found within each level. Sonic Chaos changed the figure, with access to a Special Stage being the reward for collecting 100 rings.

In the more recent game Sonic Heroes, the Special Stages made a return. These special stages were accessed by finding a key in stage 2 of each zone and keeping it (by not taking damage) until the end of the level. It consisted of running through a twisting tube. The Chaos Emerald would be ahead of the characters, and the goal was to "catch up" with it by collecting orbs which refueled a "dash gauge" which the characters would use to speed up and catch it. The stages had some motion glitches which would sometimes cause the characters to slow down dramatically, making it difficult to complete the stage. If the Chaos Emerald got to the end of the stage before the characters caught up with it, the stage would end without the gaining of a Chaos Emerald.

Super Transformation
Since the 16-bit version of Sonic the Hedgehog 2, Sonic has had the ability to transform into the extremely fast and nearly invulnerable Super Sonic once all seven Chaos Emeralds are collected. After that, Super Sonic can be used in any of the following levels once 50 rings have been collected, although one ring is lost for every second Sonic remains in this form.

In the Sonic Adventure titles, the Special Stages were omitted entirely and Chaos Emeralds were collected in non-interactive cut-scenes as part of the story, with Super Sonic only appearing in the climactic final boss fights. This dismayed many fans, who appreciated the additional replay value offered by retrying a game's levels with Super Sonic's additional abilities. Despite several games since returning to the emerald-collecting of the 2D platform titles (including the Advance series, Heroes, and Rush), Super Sonic was again only playable at the end of the game in an extra zone.

However, much to the appeal of old-time players, Sonic Colors returned the ability to access a Super transformation in normal levels. It was also one of the few recent games to omit a Super transformation from the final boss battle.

In Sonic Riders, Super Sonic is also an unlockable character, playable outside the final level for the first time since the Sega Genesis games. As with previous games, Super Sonic consumes rings as long as the form is sustained, and Sonic reverts to standard Sonic when he runs out of rings. He is playable by unlocking the "Chaos Emerald" gear. This mode of play is very difficult to play, however, due to the use of Rings as "air" in the game. Using the air features would deplete Sonic's Ring count at an accelerated rate, often leaving Sonic to run on foot until he could get more Rings to resume his Super State.

Other characters have also been able to utilize the Super transformation. In Sonic & Knuckles, Knuckles the Echidna could also transform into Super Knuckles. By locking-on Sonic & Knuckles to Sonic the Hedgehog 3, Hyper Sonic, Super Tails and Hyper Knuckles also become available, by collecting all 7 Super Emeralds in addition to the 7 Chaos Emeralds. In Sonic Adventure 2, Super Shadow also appeared at the end of the Last story, who fought alongside Super Sonic to destroy the Biolizard. In Sonic Rush and Sonic Rush Adventure, Burning Blaze appears for the extra boss, similar to the end of Sonic Adventure 2. It is named "Burning" instead of "Super" as she uses the Sol Emeralds instead of the Chaos Emeralds. In Sonic the Hedgehog (2006), Super Silver appears along with Super Sonic and Super Shadow.

A feature unique to Sonic is his ability to use Super transformations using different sources of power other than the Chaos Emeralds, each with its own unique abilities. For Sonic and the Secret Rings, Sonic used the World Rings to become Darkspine Sonic. In Sonic Unleashed, Sonic had the ability to turn into Sonic the Werehog from the power of Dark Gaia. In Sonic and the Black Knight, Sonic transforms into Excalibur Sonic using the power of the sacred swords.

Music

 * See also: List of songs

The music of the Sonic series is considered one of the aspects that make the series popular. Sonic games have featured tunes composed by a variety of people; Masato Nakamura of J-pop band Dreams Come True was responsible for the music of the first two 16-bit games. Ys/Streets of Rage composer Yuzo Koshiro composed the music for the first 8-bit title, barring what was taken from the 16-bit title. Sega's in-house music company, Wavemaster, did the majority of the music in later titles. One Wave Master employee, Jun Senoue, is part of the band Crush 40, and through his ties to the band they have played the main theme tunes of the two Sonic Adventure games, Sonic Heroes, and Shadow the Hedgehog. Heroes and Shadow the Hedgehog also featured other bands, such as Julien-K. Richard Jacques, a frequent composer of music for Sega's games, contributed to the soundtracks of Sonic R and the Saturn/PC version of Sonic 3D Blast.

Most Notable Sonic Games
Here's a list of the most notable Sonic games of each year.

Characters
Since Sonic's first appearance in 1991, many more characters have appeared and most of them have been added to main cast. Many of these characters have garnered steady fanbases since their inclusion into the franchise, while other longtime fans have criticized them for allegedly taking the gameplay focus off Sonic. Here are the main characters arranged in order of appearance:

Regional variations
To create distinctive Sonic products in various markets, Sega initially developed two different back-stories for the instruction booklets; the Japanese version (which is considered the "true" canon by most fans), and a localized version for most other regions, which was the version built upon by the comics, cartoons, and other media. As of Sonic Adventure, the storyline took a more unified approach and this practice diminished.

Differences between early regional storylines include the setting of the game (while the non-Japanese versions had the game set on a fictional planet called Mobius, the Japanese versions imply the games are set on Earth), as well as Dr. Eggman's name, which was Dr. Ivo Robotnik in most countries. (Although now, Robotnik is considered last name while Eggman is a nickname taken after his shape.)

Chronology
Notification: This chronology is not absolutely official and uses some speculation to piece titles together; it is primarily compiled using the initial order of official release as basis, then shuffling a few titles behind only if there is sufficient reason that it cannot take place in its original release period. Titles marked by an asterisk (*) are considered main series titles and have been deemed to be the highest canon; those without an asterisk have unknown relevance in the series' current canon, as they are generally not believed to be factored in ongoing game or story development. Feel free to discuss disputes and suggest revisions on the Talk page.

Classic Era
This is where the Sonic series begins. As these are earlier video games, plot lines and character backgrounds are generally given in the instruction manuals. These occasionally tend to differ between Japanese and Western releases; as the developers are usually Japanese, the Japanese storyline takes precedence over respective localizations when significant differences exist, as they conform most accurately to the series' current canon as intended.


 * Tails Adventure (Game Gear; 1995)
 * Although there are power-ups named after Sonic, Knuckles and even Fang, Tails has not directly met Sonic yet in this game according to the Japanese storyline. This is considered to be the earliest game in the series because the Japanese storyline also suggests that most of the Chaos Emeralds have been resting on Cocoa Island since ancient times, meaning that it must predate other appearances of the Emeralds.


 * Sonic the Hedgehog* (Genesis/Mega Drive; 1991)
 * Sonic the Hedgehog establishes the main canon's foundation. It introduces the protagonist, Sonic the Hedgehog, a speedy blue hedgehog and the antagonist, Dr. Ivo Robotnik, a malevolent human scientist. When Sonic realizes that his friends on South Island are in danger, he embarks on a quest to stop Robotnik, collecting the six Chaos Emeralds along the way. At the end of the game, Robotnik is defeated and the island is restored to tranquility with the power of the Emeralds. Basic gameplay elements and bosses introduced in this game have since become a staple of the Sonic series. The Master System version of Sonic the Hedgehog and its Game Gear port follow the same basic storyline, although it was released later and is considered a separate title. It is likely an alternate version of the same events or takes place directly afterwards.


 * Sonic the Hedgehog CD* (Mega CD/Sega CD; 1993)
 * This game introduces the star-crossed Amy Rose and the advanced Metal Sonic, who would later make recurring appearances throughout the series. The placement of this game's events is much debated, as there is no clear spot for it in the official timeline outside the fact that it takes place sometime before Sonic the Hedgehog 4: Episode I. It is generally assumed to take place before Sonic the Hedgehog 2, based on the fact that both games started development at around the same time, the Spin Dash is somewhat primitive, the aesthetic is closet to the first game, and Tails did not originally make a major appearance. It was later revealed in Sonic the Hedgehog 4: Episode Metal that Metal Sonic had remained defunct on Little Planet since his defeat. As Sonic the Hedgehog 2, Sonic the Hedgehog 3 &amp; Knuckles and Sonic the Hedgehog 4 take place in close proximity to each other, this placement is the most practical. Tails' two cameos (once in the Tornado) can be chalked up as time travel shenanigans or outside the overall storyline.


 * Sonic the Hedgehog 2* (Genesis/Mega Drive; 1992)
 * This game is the formal introduction of Miles "Tails" Prower, marking the first time he met Sonic. He would go on to appear in most titles along his new best friend. In the game, Dr. Robotnik follows Sonic's plane, the Tornado, to West Side Island on a hunch. While there, he gets a reading that the six Chaos Emeralds have relocated themselves within the island's depths, along with a lost seventh Chaos Emerald spoken of in the island's legend. He launches his space station, the Death Egg, and sets his eyes on the seven Chaos Emeralds to fuel its weapons. Sonic and Tails set out to find the Emeralds and stop the Death Egg from threatening to the world. As the seven Emeralds appear together here, Super Sonic makes his first appearance.


 * Sonic the Hedgehog 3 &amp; Knuckles* (Genesis/Mega Drive; 1994)
 * Sonic the Hedgehog 3 & Knuckles comes shortly after the events of Sonic the Hedgehog 2 (either some days later or immediately afterward depending on the source), and recycles its game engine core. The combined game is considered canonical as it is closer to the way the designers intended; otherwise, Tails vanishes and Sonic loses the Chaos Emeralds without explanation. The game introduces Knuckles the Echidna, the guardian of the Floating Island (later renamed Angel Island) and the Master Emerald. Dr. Robotnik intends to steal the Chaos Emeralds as energy for the repaired Death Egg by tricking Knuckles into believing Sonic and Tails are his enemies, and when that begins to fail he sets his sights on the Master Emerald. Within the game, Sonic and Tails' story seems to happen, then Knuckles' story. In Sonic and Tails' story, the Floating Island is in the ocean and Knuckles is their enemy; in Knuckles' story, the Floating Island is floating in the sky and Sonic is his ally.


 * Sonic the Hedgehog 4: Episode I* (iOS, Wii, PS3, 360; 2010) (PC, Android; 2012)
 * While this game uses "modern" rather than "classic" designs (later implied in Sonic Generations to be younger forms of the redesigned characters rather than a mere art style change), this game takes place firmly after Sonic the Hedgehog 3 & Knuckles, as Dr. Eggman's profile on the official website states that he lost the Master Emerald during his last encounter with Sonic. After surviving from the destruction of the Death Egg, Dr. Eggman recreates some of his older inventions to have revenge on Sonic.


 * Sonic the Hedgehog 4: Episode II* (PC, PS3, 360, iOS, Android; 2012)
 * This game picks up a few months after Episode I and reveals Eggman's true plot, showing why Eggman was investigating Lost Labyrinth and why he built Mad Gear. When "locked-on" to Episode I of the same platform, it opens the Episode Metal scenario, which takes place shortly before Episode II and reintroduces Metal Sonic since his crushing defeat in Sonic the Hedgehog CD. At the end, Death Egg mk.II is shut down, but whether Little Planet was truly freed from Eggman's grasp remains to be seen.


 * Sonic the Hedgehog 2  (Master System, Game Gear; 1992)
 * In this game, Sonic returns to South Island to find it invaded once again by Dr. Robotnik. Additionally, Tails is kidnapped by Dr. Robotnik, and is used as a bargaining chip for Sonic to collect the Chaos Emeralds for him. While this game was released before the 16-bit Sonic the Hedgehog 2, it is considered to take place afterwards because Tails met Sonic shortly before the events of that game. This marks Sonic's second appearance on South Island after having a series of adventures away.


 * SegaSonic the Hedgehog (Arcade; 1993)
 * This game is a side-story in which Eggman specifically targets Sonic, and also features the debut of Mighty the Armadillo and Ray the Flying Squirrel.


 * Sonic Chaos (Master System, Game Gear; 1993)
 * In this game, Dr. Robotnik managed to get the Red Chaos Emerald without Sonic knowing, but this caused a chain reaction of chaos energy, resulting in South Island slowly sinking into the ocean. Sonic and Tails must gather the Emeralds of the island to prevent it from being destroyed.


 * Sonic the Hedgehog Spinball (Genesis/Mega Drive; 1993)
 * Dr. Robotnik takes control of Mount Mobius, turning it into his new Veg-O-Fortress, which transforms helpless animals into robot slaves at an alarming rate. In the end, Sonic retrieves the Chaos Emeralds and takes down Dr. Robotnik once again. The original game contains cameos of characters from the contemporary cartoons and Archie comics during the bonus rounds, and the game is said to take place on Mobius - making it the only time Sonic's world is named as such in Japanese game material.


 * Sonic the Hedgehog Triple Trouble (Game Gear; 1994)
 * In this game, Dr. Robotnik has captured all of the Chaos Emeralds. Unfortunately for him, an accident during the testing phase of his weapons scatters the Emeralds across the island again. While Sonic and Tails are out to retrieve them, they are repeatedly cut short by Knuckles the Echidna. Robotnik has already reclaimed the yellow Emerald, and he's once again duped the guardian into believing Sonic and Tails are out to steal the stones. Meanwhile, a sneaky treasure hunter named Nack the Weasel (Fang the Sniper in the Japanese version) is taking advantage of the commotion to collect the Emeralds for himself. He does not know of the true power of the Emeralds, but he does know the large, pretty gems would fetch a high price. Now it's a mad multi-sided race for the Chaos Emeralds.


 * Knuckles' Chaotix (32X; 1995)
 * This game takes place on an carnival-themed island that Dr. Robotnik dubs Newtrogic High Zone, and introduces Vector the Crocodile, Charmy Bee and Espio the Chameleon to the game series, as well as returning Mighty the Armadillo. According to the Japanese manual, Metal Sonic's appearance is also explained by Robotnik building a replacement body after being damaged, called "Metal Sonic Kai" (which, contrary to popular belief, is not the name of the final boss creature, which may or may not be a transformed Metal Sonic). Note that the game's canonicity is in question since Takashi Iizuka stated that he considers the Chaotix to be re-imagined as of Sonic Heroes, although he did not go into detail. It also contains somewhat contradictory storylines and is evidently not a priority in re-releases, rendering this game "pseudo-canon" at best.


 * Tails' Skypatrol (Game Gear; 1995)
 * As mentioned in the game's manual, this solo title takes place while Tails is on his own, at least sometime after his first adventures with Sonic. While flying, he spots a solitary island which he initially believes is a new base of Dr. Eggman, but instead it belongs to Witchcart. Wanting to be the hero, he propels into action.


 * Sonic Labyrinth (Game Gear; 1995)
 * This game is one of the few Sonic titles since Tails' debut in which he is absent, but this is explained by the above title which shows Tails on his own. Dr. Robotnik finally realizes that Sonic's speed is key to the doctor's failures, so he creates the Slow-Down Boots with chaos energy to replace his trademark sneakers. While imprisoned within his artificial labyrinth on South Island, Sonic discovers that he can still Spin Dash, so he uses that to his advantage to stop the bad doctor once again.


 * Sonic the Fighters (Arcade; 1996)
 * Dr. Robotnik has built the Death Egg II and Tails' Lunar Fox is a single-seater. Therefore, the heroes hold a tournament to see who is worthy of going to space to foil Robotnik's plans. This game introduces Bark the Polarbear and Bean the Dynamite, as well as Tails' reconnaissance robot Mecha Sonic Model No.29. The game also establishes certain elements seen later in Sonic Adventure, such as Amy's Piko Piko Hammer and Tails' Workshop and his tail whip attack. It should be noted that this game features eight Chaos Emeralds; this can be explained by one of them being the Master Emerald, as it was described as a large Chaos Emerald in earlier material. It is also shown to change size in later games, and the concept of a fake Emerald didn't exist yet.


 * Sonic 3D Blast (Genesis/Mega Drive, Saturn; 1996)
 * Dr. Robotnik discovers that the Flickies of Flicky Island can travel between dimensions via large rings. He theorizes that he can use their abilities to locate the Chaos Emeralds, so he turns them into robots to resume his search for the Emeralds. Sonic travels through the island, freeing every single Flicky he comes across. Along the way, Tails and Knuckles help him find the Chaos Emeralds.


 * Sonic Blast (Game Gear; 1996)
 * While this game was released at the end of 1996 in conjunction with the similarly named Sonic 3D Blast, it is worth noting that both games have little in common (it also has an entirely different name in Japan). No enemies, levels, or bosses, are shared between the games. The story is also completely different. Sonic and Knuckles join together to collect five pieces of a Chaos Emerald, which was accidentally shattered by Robotnik when he aimed for Sonic.


 * Sonic R (Saturn; 1997)
 * In this game, Sonic joins the World Grand Prix in a race for the seven Chaos Emeralds. Knuckles and Amy, knowing of Robotnik's plans, join in as well. The game featured a few new characters to the series: Metal Knuckles and Tails Doll. These two never made another appearance, except as look-alike target practice dummies in Sonic Adventure. Additionally, EggRobo, a robot version of Dr. Robotnik from Sonic the Hedgehog 3 & Knuckles, was a playable character as well.

Modern Era
Following the noticeable lack of a real main title for the Sega Saturn generation, Sonic Team reinvisioned the series' setting and characters to adapt to a growing 3D market. At this point, storylines are made more clear within the games themselves, and for the most part there was a more unified effort at Sega to maintain a consistent continuity.


 * Sonic Adventure* (Dreamcast; 1998)
 * Adventure marks the first of the "evolved" fully 3D Sonic games. Sonic Adventure is closely connected to Sonic the Hedgehog 3 & Knuckles, as seen by the fall of Angel Island and its lore. It also makes several references to earlier games - Sonic making jokes at Knuckles' expense about his history with Robotnik (or Eggman); Tails' dream of when he first met Sonic; Amy's fantasy flashback of Sonic rescuing her from Metal Sonic; icons of their original designs in places like slot machines; etc.


 * Sonic Shuffle (Dreamcast; 2000)
 * The story involves Sonic and company getting caught up in a mess in a world called Maginary World, which they inadvertently stumble upon one day. A villain named Void has shattered the Master Precioustone into many pieces, resulting in chaos in every part of the world. Lumina Flowlight and the rest of Maginary World are counting on Sonic to restore it and bring Illumina back, who mysteriously disappeared after the disappearance of the Precioustone.


 * Sonic Adventure 2* (Dreamcast; 2001)
 * While the storyline has little in common with its predecessor, it clearly follows the events of its prequel due to a key mention that Tails was awarded a Chaos Emerald to celebrate his heroism. This game introduces Shadow the Hedgehog, a 'look-alike' of Sonic, Rouge the Bat, a rival treasure hunter for Knuckles, and a playable Dr. Eggman, whose genius is now up against Tails.


 * Sonic Advance (GBA; 2001)
 * In this game, Dr. Eggman goes back to his roots and concocts the same old scheme: keep Sonic distracted with his robots while he tracks down the Chaos Emeralds. This time, Sonic is joined by his friends Tails, Knuckles and even Amy, and Sonic is first shown grinding without his Soap shoes.


 * Sonic Advance 2 (GBA; 2002)
 * Eggman's strategy is essentially unchanged from Sonic Advance, but this time he tries kidnapping Sonic's friends (or in the case of Knuckles, tricking him to join his cause). This marks the official introduction of Cream the Rabbit, her Chao Cheese and mother Vanilla. She also appears in remakes of Sonic Adventure, but does not interact with the cast in any way.


 * Sonic Pinball Party (GBA; 2003)
 * The story is set in Casinopolis (presumably the same one in Station Square), where Dr. Eggman turns the people gambling into robots. He brainwashes Miles "Tails" Prower and Amy Rose. Sonic must save his friends by winning a pinball tournament called the "Egg Cup Tournament."


 * Sonic Heroes* (GCN, Xbox, PS2; 2003)
 * It continues after the storyline of Sonic Adventure 2, reintroducing Shadow the Hedgehog since his fall from the ARK, as well as three Chaotix characters who have joined as a detective team. The game stars Metal Sonic as the antagonist of the game rather than Dr. Eggman, who is actually held captive and being impersonated. Metal Sonic manipulates the characters into giving him strength, but in the end he is thwarted by the Chaos Emeralds, which he left out of the equation. This is notably the game right after Sonic Adventure 2, as Sonic has not been active for a while at the start of the game.


 * Shadow the Hedgehog* (GCN, Xbox, PS2; 2005)
 * This game takes place between Sonic Heroes and Sonic Battle, showing a Shadow who is reawakened but devoid of most of his memories. The game features multiple storyline paths depending on the player's actions which lead to ten different conclusions that seem to be distorted scenarios before the final story is unlocked, revealing the true outcome of the game.


 * Sonic Battle (GBA; 2003)
 * Even though this game was released before Sonic Heroes, it comes afterwards due to Shadow acting like himself again, references to him saving the world and Rouge commenting that Chaos Gamma (whom she believes to be a mere Guard Robo) looks like Omega. It introduces the Gizoid, a robotic artifact of an ancient civilization that Sonic dubs "Emerl".


 * Sonic Advance 3 (GBA; 2004)
 * While this game is the last in the Sonic Advance trilogy, its storyline closely follows Sonic Battle, as Eggman used Emerl's battle data to construct Gemerl. In this game, Eggman has torn the planet into separate dimensional zones, and Sonic and Tails must reunite with their allies and use teamwork to fight off Eggman and reform the world.


 * Sonic Rush (DS; 2005)
 * Blaze the Cat, the princess of another dimension and guardian of the Sol Emeralds, is introduced. It also introduces Eggman Nega, who claims to be a counterpart of Eggman from that same dimension.


 * Sonic Riders (GCN, Xbox, PS2; 2006)
 * This game introduces the Babylon Rogues: Jet the Hawk, Wave the Swallow, and Storm the Albatross. Jet and Sonic seem to have a rivaling relationship over who is the fastest thing alive, and, in the end, Babylon Garden's secret treasure is uncovered after defeating the Babylon Guardian.


 * Sonic the Hedgehog (360, PS3; 2006)
 * This game introduces a version of Silver the Hedgehog, a hedgehog from the future who is duped into believing Sonic is the one who ruined his world. The placement of this game in the timeline is debatable due to the confusion regarding the characterization of Blaze the Cat; she shows up in Silver's future without explanation, seemingly recognizes Sonic (but apparently not vice versa) and is last seen sealing herself in another dimension with Iblis (which fails). The game also features a known time paradox involving the Blue Chaos Emerald, but in the end the game resolves itself by technically removing itself from the timeline. However, although the game "didn't happen", it still seems to be a part of canon; when Crisis City is revisited due to the time displacement shown in Sonic Generations, Blaze remarks that she didn't believe she'd see that place ever again. It has also been confirmed that Blaze has always been from the Sol Dimension, which also reflects the official profile she was given in this game's website, leaving how and why she was ever in Silver's future a mystery. However, given that some official profiles state she can manipulate the spacetime properties of the Sol Emeralds, it can be assumed she appears in this game and certain later titles via her Sol Emeralds. Another mistake seems to be that Princess Elise is still wearing a dress modeled after Solaris in the game's ending in the redone present, although whether this is truly a mistake or a hint of something else sinister (such as the identity of the Time Eater) is yet to be revealed.


 * Sonic Rivals (PSP; 2006)
 * In this game, Silver the Hedgehog is reintroduced from a good future, revealing that Eggman Nega is also from his time period. Masquerading as Dr. Eggman in the past, he uses a special camera to turn everyone into cards on Onyx Island, an island he brought along with him from the future. His master plan is to change his destiny by turning the whole planet into a card that he can control. It is revealed that he was never an alter ego, but rather a descendant of Eggman who is ashamed of his ancestor's failures.


 * Sonic and the Secret Rings (Wii; 2007)
 * Sonic enters the world of Arabian Nights, a book that appears in front of him. He journeys to save the world of Arabian Nights, as well as his own life and his new friend, Shahra the Ring Genie, from the evil genie, Erazor Djinn, from the story of Aladdin. In the end, Sonic and Erazor Djinn each use powers from the Seven World Rings and transform into Darkspine Sonic and Alf-Layla-wa-Layla, respectively. Darkspine Sonic defeats Alf-Layla-wa-Layla, then they turn back to normal. Using his wishes, Erazor Djinn is forever sealed away inside his lamp and Shahra and the story are saved. Sonic eventually finds a way back to his own world, and the name of the book changes from "Aladdin and the Magic Lamp" to "Sonic and the Secret Rings".


 * Sonic Rush Adventure (DS; 2007)
 * This game shows the Sol Dimension for the first time, and marks the next real time Sonic and Blaze directly meet after the events of Sonic Rush. While Eggman and Eggman Nega are working together again, they are defeated, and the possibility for Blaze to meet Sonic and his friends again opens up.


 * Sonic Rivals 2 (PSP; 2007)
 * This game introduces Metal Sonic 3.0, which is a robot built by Eggman Nega. Because Dr. Eggman is not the main antagonist of the game, he sends Metal Sonic as to help fight against the threat of Eggman Nega. Silver again makes another appearance in this game and this time Eggman Nega receives a sound (but not necessarily final) defeat.


 * Sonic Riders: Zero Gravity (Wii, PS2; 2008)
 * The game continues the story of the Babylon Rogues last seen in Sonic Riders. The major focus off the game is on the Arks of the Cosmos.


 * Sonic Unleashed* (Wii, PS2, 360, PS3; 2008) (Mobile phones; 2009)
 * Before he can stop Dr. Eggman's evil plans once again, Super Sonic is engulfed by the dark energy of Dark Gaia, a creature that prematurely awakens from the center of the Earth and rips the world into several pieces. As a result, when the day turns to night, Sonic undergoes a transformation in which he becomes a Werehog. Eventually, Dark Gaia absorbs its dark energy that resides inside of Sonic, putting a stop to the Werehog transformation. In the end, Dark Gaia is defeated by Super Sonic and Light Gaia, and the world is restored to normal.


 * Sonic and the Black Knight (Wii; 2009)
 * Sonic is magically summoned by Merlina to save her Arthurian world from the reign of King Arthur, the Black Knight. By the end, it is discovered that King Arthur was an illusion conjured up by Merlina's grandfather, Merlin. Taking the Black Knight's Scabbard, Merlina planned to make the world eternal by using the power of the underworld. With the help of the Knights of the Round Table (Sir Gawain, Sir Lancelot, and Sir Percival), and the Lady of the Lake (all with an uncanny resemblance Sonic's real friends just like the previous storybook adventure), a barrier was formed around the castle to stop the spread of the underworld using the four legendary swords. Although the barrier was weak, Sonic jumped in with Caliburn, and fell to the Dark Queen - the now-powerful Merlina with the Scabbard. After breaking Caliburn, the Dark Queen easily overpowers Sonic. His will to keep fighting returns the light to the sacred sword, revealing Caliburn to be Excalibur when the Lady of the Lake has Lancelot, Gawain, and Percival throw their swords - Lancelot's Arondight, Gawain's Galatin, and Percival's Laevatein - into a portal, which fuse with Caliburn and cover Sonic, ultimately transforming him into Excalibur Sonic. In the end, the Dark Queen is defeated and Sonic is thought to be the true King Arthur. Additionally, the name of the book changes from "King Arthur and the Knights of the Round Table" to "Sonic and the Black Knight". While this happens, Amy Rose is also heard saying that she doesn't believe Sonic's story, thinking it was a way to get himself out of their date (which is an optional event they apparently agreed upon during the previous title).


 * Sonic Free Riders (360; 2010)
 * The game takes place during the next World Grand Prix, which was hinted at the end of Sonic Riders: Zero Gravity.


 * Sonic Colors* (Wii, DS; 2010)
 * The two versions of the game (Wii and DS) have the same storyline with slight differences between them. Continuing from Sonic Unleashed, Sonic Colors is a high speed action-adventure in which Sonic races through theme park-inspired worlds to rescue a colorful alien race from the clutches of Dr. Eggman. An extraordinary amusement park has been seen orbiting around the home planet of Sonic the Hedgehog, and rumors are spreading that an alien race of Wisps, who have a unique colorful energy, are being held captive there by the evil Dr. Eggman. Soon after arriving at the amusement park, Sonic discovers he is able to use these mysterious alien forces to help the Wisps escape. Through the game in both versions Sonic races around the park saving the Wisps with Tails as his partner. Aside from Sonic, Tails and Eggman, there aren't any other recurring characters present in the Wii version. The DS version contains gratuitous cameos from other characters such as Knuckles, Shadow, Amy, Blaze, and Silver. The Wii version the game ends after clearing the Terminal Velocity area, but the DS version features the semi-traditional Last Story in which Sonic becomes Super Sonic to defeat and purify the Mother Wisp, who has been corrupted into the Nega-Mother Wisp by Dr. Eggman.


 * Sonic Generations* (360, PS3, PC, 3DS; 2011)
 * Sometime after the events of Sonic Colors, Sonic celebrates his birthday until his universe is thrown into chaos when a mysterious new power creates "time holes", which pull Sonic and his friends back through time by a mysterious new nemesis. As a result, he encounters some surprises from his history, including Classic Sonic: Sonic as he was in the past. After finding out everything is chalk white and losing color, Modern Sonic and Classic Sonic team up to defeat this strange new enemy, save their friends, and find out who is really behind this diabolical deed. It is also interesting to note that Dr. Eggman left Cubot and Orbot in space after the events of Sonic Colors, meaning that it likely takes place directly afterwards - although, since time travel is involved, that may not necessarily be the case. It is also unknown at which point the Classic Sonic, Tails and Robotnik come from, but it is implied that Sonic has just started his first adventure or just had his adventure with Tails, and Robotnik had either just arrived at the Death Egg (console version) or is making sure it has a successful relaunch (3DS version). Sonic Team's console version is often considered the "true" version, as Dimps' 3DS version contains far less original elements and is deemed more of a "budget" title.


 * Sonic Lost World* (Wii U, 3DS; 2013)
 * After the events of Sonic Generations, Sonic and Tails took to the skies and chased after Dr. Eggman and his robots (whose latest misdeed is capturing animals as Badnik fuel) while Amy and Knuckles covered the ground and encounters a mysterious floating island known as “Lost Hex,” where they runs across the Deadly Six. The Deadly Six were united under Eggman for his own needs until they betrayed him when Sonic foolishly knocked the Cacophonic Conch, so Sonic and Eggman team up together to stop them from taking Eggman's devices out of proportion. In the end, both Eggman (who betrayed Sonic) and the Deadly Six were defeated.

Miscellaneous
These entries are side-games that lack an actual storyline, and thus do not represent any true progression in the series. As part of a long-running franchise, each have the potential to fit in-continuity, but their significance is pushed to the side due to this fact.


 * Sonic Eraser (Meganet / Mega Drive; 1991)
 * This is a Japanese-only puzzle game that was distributed digitally. There is no known exact release date, so it may or may not predate Sonic's debut.


 * Waku Waku Sonic Patrol Car (Arcade; 1991)
 * A children's Arcade machine that shows Sonic as a hero cop that chases down Eggman, who is now a common thief.


 * SegaSonic Cosmo Fighter (Arcade)
 * Another children's Arcade machine that features Sonic and Tails as galactic officers hunting down the space scoundrel Eggman.


 * Knuckles the Echidna in Sonic the Hedgehog 2 (Genesis/Mega Drive; 1994)
 * A lock-on bonus that inserted Knuckles as a playable character in Sonic the Hedgehog 2, replacing both Sonic and Tails. However, Knuckles had no role in the series' storyline at this point.


 * Blue Sphere (Genesis/Mega Drive; 1994)
 * A collection of the Special Stages from Sonic the Hedgehog 3 and Sonic &amp; Knuckles, made by locking on Sonic & Knuckles with Sonic the Hedgehog. Single stage variations can also be played be locking on to any other game.


 * Dr. Robotnik's Mean Bean Machine (Genesis/Mega Drive, Game Gear; 1993)
 * A game that is expressly set in the Adventures of Sonic the Hedgehog cartoon universe. It is actually a mere localization of Puyo Puyo.


 * Sonic Drift (Game Gear; 1994)
 * This game is a racing game that includes Sonic the Hedgehog, Miles “Tails” Prower, Amy Rose, and Dr. Eggman. Seeing as how this game does not include any story, it can be seen as pure filler. It was also released between Sonic the Hedgehog 3 and Sonic & Knuckles, with a noticeable lack of Knuckles.


 * Wacky Worlds Creativity Studio (Genesis; 1994)
 * A Mario Paint-esque title that features Sega characters such as Sonic and ToeJam & Earl.


 * Sonic the Hedgehog's Gameworld (Pico; 1994)
 * An edutainment sort of game in which Dr. Robotnik appears to have constructed an amusement center ("Gameworld") in his own image. There are Chaos Emeralds hidden on each floor, so Sonic, Tails and Amy set out to clear the building's minigames and find the Emeralds.


 * Tails and the Music Maker (Pico; 1994)
 * An edutainment title and Tails' first starring role.


 * Sonic Drift 2 (Game Gear; 1995)
 * This is another racing game that is most likely pure filler due to the lack of a story. It added three new playable characters: Knuckles the Echidna, Fang the Sniper and Metal Sonic. The only thing that resembles a story is the fact that, in the game, Chaos Emeralds are awarded for winning races. If Sonic, Tails, Knuckles or Amy collects all six in the Blue GP, they will face Dr. Robotnik in a final race around the Death Egg. If Robotnik, Metal Sonic or Fang collects all six in the Blue GP, they will face Sonic instead.


 * Sonic's Schoolhouse (PC; 1998)
 * An edutainment title using Sonic's sprite asset from the unreleased Sonic X-treme (see below).


 * Sonic the Hedgehog Pocket Adventure (NGPC; 1999)
 * This game is largely a remix of Sonic the Hedgehog 2, with the addition of music from Sonic the Hedgehog 3 and Sonic & Knuckles, as well as certain elements later seen in the first two Sonic Advance games. There is no real official storyline in this game, although there is occasionally silent on-screen action that tries to tell a narrative. It can be presumed that it is the basic storyline of Eggman trying to take over South Island or West Side Island, topped with him tricking Knuckles yet again. In addition, Dr. Eggman is seen changing from his old outfit to his new outfit by the end of the game.


 * Sega Superstars (PS2; 2004)


 * Sonic X (Leapster)
 * An edutainment title loosely based on both the Sonic X anime and the Genesis games.


 * Sega Superstars Tennis (PS3, 360, Wii, PS2, DS; 2008)


 * Mario & Sonic at the Olympic Games (Wii; 2007) (DS; 2008)
 * This game lacks a story but it is the first meeting between Mario and Sonic


 * Mario & Sonic at the Olympic Winter Games (Wii, DS; 2009)
 * This game would occur after the events of the previous Olympics event.


 * Mario & Sonic at the London 2012 Olympic Games (Wii; 2011) (3DS; 2012)
 * This game does include a story mode, but only in the Nintendo 3DS version.


 * Mario & Sonic at the Sochi 2014 Olympic Winter Games (Wii U; 2013)
 * The fourth title in the crossover series.


 * Super Smash Bros. Brawl (Wii; 2008)
 * Sonic appears at the end of The Subspace Emissary, but the Smash Bros. series is highly implied to take place in its own universe.


 * Sonic & Sega All-Stars Racing (360, PS3, Wii, DS, PC; 2010)
 * A game very similar to Mario Kart, you play as notable SEGA characters and race against each other.


 * Sonic & All-Stars Racing Transformed (360, PS3, Wii U; 2012) (3DS, PC; 2013)
 * The sequel to the above.


 * Sonic Athletics (Arcade; 2013)
 * A treadmill with a screen depicting a Sonic character as the avatar.


 * Sonic Ghost Shooting (Arcade; 2013)
 * An Arcade game based on the haunting segments of Sonic Adventure 2.


 * Various officially-licensed miscellaneous titles
 * This includes LCD products (for example, Amazing Sonic), online games (like Sonic Tweet) or mobile phone apps (such as the Sonic Jump series and its successor, Sonic Dash).


 * Sonic Chronicles: The Dark Brotherhood (DS; 2008)
 * A spin-off RPG title made by BioWare. Unlike the rest of the titles in this category, it does feature a storyline, which introduced a number of new characters as well as explaining certain mysteries from previous titles. The story revolves around the Twilight Cage, a realm where powerful beings/races who threaten the peace of the world are sealed away by the god figure Argus. Trapped in the realm, Sonic and friends save the day and escape, only to find that Dr. Eggman has managed to rebuild his forces, having taken advantage of the amount of time that passed by while they were trapped inside the Twilight Cage (since time moves slower in the Twilight Cage). The game was supposedly meant to have a sequel which was never developed. As it is also set two years after Dr. Eggman's last defeat, it is unclear if it takes place at the end of the series, or if it conveniently leads into the introduction of Sonic Unleashed.

Cancelled
These are some (but not all) known titles that have been cancelled. As elements may have been reused in released games, they are unlikely to be revisited.


 * Sonic the Hedgehog (Amiga)
 * A version of Sonic the Hedgehog for the Amiga computer. It is unknown if it would have been a port or an original title like the 8-bit game.


 * Sonic's Edusoft (Master System)
 * An edutainment title starring Sonic and using some graphics from the 16-bit game.


 * Sonic the Hedgehog 3 Limited Edition (Genesis/Mega Drive)
 * The complete form of Sonic the Hedgehog 3 and Sonic & Knuckles in one cartridge. Rendered obselete now due to compilations.


 * Sonic Crackers (Genesis/MegaDrive)
 * Sonic and Tails are joined together with a band of rings. The concept was reused as Chaotix, with Sonic replaced by Mighty and Tails removed.


 * Sonic X-treme (Saturn, PC)
 * Possibly the most well-known canned Sonic game, as it was intended to be a killer app of the Saturn. Many storylines were considered for this game, including the introduction of a new love interest called Tiara Boobowski. It also went through several development phases, including a SatAM-based game. Chris Senn attempted an unofficial revival in the mid-2000's, but it was also abandoned - although there is at least one fan-project to recreate the game as closely as possible using the leaked development assets.


 * Sonic the Hedgehog Extreme (Xbox)
 * A boarding proof of concept using some Sonic Adventure 2 assets that was likely converted into Sonic Riders.


 * Sonic DS (DS)
 * A Nintendo DS tech demo that used the Touch Screen. It was replaced by Sonic Rush.

Spin-offs
The Sonic video game franchise has led to a large number of spin-offs in other media starring Sonic. Each spin-off incorporates aspects from the games to varying degrees. With few exceptions, each production takes place in their own fictional universe, independent of the video games.

Animations
Adventures of Sonic the Hedgehog (or AoStH for short) is an American animated television series that was first broadcast in September 1993 and has been running in cartoon syndication ever since. It follows the escapades of Sonic and Tails as they stop the evil Dr. Ivo Robotnik and his array of vicious robots from taking over the planet Mobius. The plots very loosely followed the storyline of the video games series; at the time the Sonic games were still quite new and lacking much plot or character development, which was in turn filled in by the show's writers.

The animated television series simply called Sonic the Hedgehog originally aired from September 1993 to June 1995. While Adventures of Sonic the Hedgehog is known for its bright colors and whimsical humor, Sonic the Hedgehog featured darker stories which constituted a departure from the tone of the Sonic games of the time. To distinguish between the two series, fans typically refer to this series as SatAM because it was a Saturday morning cartoon while Adventures of Sonic the Hedgehog aired on weekdays in syndication and using the show's full title would cause confusion in many situations because the show's title is the same as the character's name.

A two-episode OVA film series based upon the game Sonic the Hedgehog CD and the video game series as a whole, Sonic the Hedgehog: The Movie was made in Japan in 1996 and released as a dub in North America in 2000. Unlike the games, the film takes place on a world named Planet Freedom that, as with many anime series, appears to be a crossbreed of a fairytale land and Earth. At the time of its creation, the anime did not differ as far from official canon as it does today; at this point, it could be considered to take place in an a different continuity than the games, just like other versions of Sonic from other media.

The cartoon Sonic Underground ran for only one season, 1998 to 1999; it bears little relation to other entries featuring Sonic (including previous games, comics and the other animated series) and shares few established characters. 65 episodes were originally produced and of those, only 40 were released. Unlike its predecessor, SatAM, the heroes do not remain in a sanctuary-like refuge but instead travel around Mobius to battle Robotnik's forces on a global scale. The Mobian civilization featured in the series includes multiple cities, a poor underclass and an aristocracy for the heroes to interact with. Sonic Underground is the only animated series based on Sonic where Tails has not made an appearance.

The anime Sonic X is the longest-running and most successful animated series based on Sonic to date. Originally planned as a 52 episode series that would be inspired by the story lines of the Sonic Adventure series, Sonic X has now expanded to 78 episodes with the latest 26 episodes set primarily in outer space. Sonic X is also the only animated series to include Super Sonic. Despite these similarities, it is not completely compatible with the video game canon if only for the fact that it shows Sonic being transported to Earth from another world; in the games, Sonic has always lived on Earth.

Comics
The Sonic the Hedgehog manga series, published in Shogakukan's Shogaku Yonensei (literally "fourth-year student") was written by Kenji Terada and it was illustrated by Sango Norimoto. The manga, which started in 1992, was about a hedgehog boy named Nicky who can turn into Sonic the Hedgehog. Sonic fights Dr. Robotnik, with Tails tagging along to help him.

Sonic the Comic, known to its many readers as STC, was a UK children's comic published by Fleetway Editions between 1993 and 2002. Although it was the UK's official Sega comic, Sonic the Comic established its identity and ongoing storyline and setting when Sonic, Tails and their friends were sent forward in time six months. During their absence, Doctor Robotnik successfully conquered the entire planet of Mobius, and Sonic's group were forced underground, operating as "freedom fighters" attempting to bring down Robotnik's rule of the planet. Due to an aggressive series of budget cuts on the part of Fleetway, the series went into full reprint by issue 184; the final story ended with a number of loose ends left untied. An online fan based comic, called STC-Online, has been set up to continue the STC story starting from where the original STC story left off and beginning with issue 224, due to STC being reprints from issues 185 to 223. It has received positive feedback from both fans and writers of the original STC.

Sonic the Hedgehog is an ongoing series of American comic books published by Archie Comics All of Archie's Sonic-related series, miniseries and specials take place in the same fictional universe. This universe features a mixture of characters, settings and situations from the video games, the SatAM cartoon, the various other incarnations of Sonic, and many elements unique to the comic universe. The current status quo of the comic deals with a full-scale war between the Eggman Empire, ruled by Robotnik, and the restored Kingdom of Acorn, which is protected by Sonic and his various allies. However, it also features a variety of other villains and heroic characters whom Sonic and the other Sega characters interact with.

Sonic X is the title of a comic book series that exists to supplement the stories from the animated series of the same name. It began in September 2005 and was originally meant to be a four-part series; due to the positive reaction to the series' announcement, it was extended to ongoing status before the first issue premiered. The comic is unique in that it is not directly based on the games; the comic is based on the television show and takes place in its expanded fictional universe. The comic borrows elements from the series first two seasons of the show, including Eggman's fort, destroyed in Season One in the Series, and characters from the Sonic Adventure storyline.

Reception
The Sonic the Hedgehog series became an instant success throughout the video game industry. It leads as a legendary icon throughout the first game, hitting a mega-sensation and becoming the most popular game franchise at that time. The series ranks 12th as the best selling franchises being 80,000,000 sold worldwide. The series have won several awards as well. It won "Oustanding Contribution" by the Golden Joystick, the first ever to win that prize. It got Walk of Game, has one several graphic, gameplay, game of the year, and sound awards almost per game. The Sonic the Hedgehog franchise was awarded seven records by Guinness World Records in Guinness World Records: Gamer's Edition 2008. The records include "Best Selling Game on Sega Systems", "Longest Running Comic Based on a Video Game" and "Best Selling Retro Game Compilation" (for Sonic Mega Collection). In the Guinness World Records: Gamer's Edition 2010, the Sonic the Hedgehog series was listed number 15 out of the top 50 video game franchises. In December 2006, IGN ranked Sonic the Hedgehog as the 19th greatest series of all time, claiming that "although recent 3D entries in the series have been somewhat lacking, there is no denying the power of this franchise."

Besides this praise, the Sonic the Hedgehog series are somewhat known to be hated and are controversial. Controversy also hits the annoying fanbase claimed by people. A common criticism has been that the variant gameplay styles found in recent 3D titles have strayed from the formula of the original series. Specifically, the series' jump to 3D has been noted as a declining point. In late 2010, Sega delisted several below average Sonic titles, such as the poorly received Sonic the Hedgehog (2006), in order to increase the value of the Sonic brand after positive reviews for the games Sonic the Hedgehog 4 and Sonic Colors. Such small games like Sonic Free Riders won Sh**tiest game of the Year by ScrewAttack and listed Series that should Die by Yahoo! experts. GameTrailers named it first as Worst Blockbuster Franchise ever. People claim that "Sega’s speedy mascot has had a hard time recapturing the form that put him on top of the gaming world in 1991."

Despite some of its more scathing contenders, the Sonic the Hedgehog series still maintains a global position on among gamers, it still has a very supportive fanbase and has continued to run strong up to this day.

Notes and references

 * In addition to information taken from the Sonic the Hedgehog games themselves, the instruction booklets of the US and Japanese versions of the games were also used as references for this article.