Knuckles the Echidna (Sonic X)

Knuckles the Echidna (ナックルズ・ザ・エキドゥナ) is one of the main characters in the anime series Sonic X and its comic series published by Archie Comics. He is an anthropomorphic echidna, famous as a treasure hunter and a master of martial arts. Knuckles' primary ability is strength, his arms are so powerful that he can shatter rocks. Ever since the first Chaos Control incident, Knuckles has become dedicated to finding the Chaos Emeralds so he can go back to his job of guarding the Master Emerald as soon as possible which he takes very seriously.

Past
Knuckles hails from an unnamed world in a parallel dimension to Earth.

New World Saga
When Sonic attacked Eggman's headquarters late one night, Amy and Tails nearly crashed into a large rock after the Tornado 2 was wounded by gunfire from Eggman's guard robots. Luckily, Knuckles smashed the rock to pieces, allowing the Tornado 2 to land safely. When Chaos Control occurred shortly after that, Knuckles was swept up in it alongside Tails and Amy.

Knuckles and Amy ended up in the sewers of Station Square on Earth, trying to find some way to get home, especially as Knuckles still had his duties to protect the Master Emerald to think about. However, at one point, they were forced to the surface when Dr. Eggman attacked Station Square with E-23 Missile Wrist, proving more than a match for the Station Square Police Department. Upon witnessing the destruction, and Tails fighting Missile Wrist in the Tornado 2, Amy headed to the roof, leaving Knuckles to follow via the stairs, making it to the roof before Amy, but he was unable to stop her from attacking Missile Wrist and being taken prisoner, with Eggman threatening to have her squeezed to death if Knuckles tried to help. Thankfully, Sonic arrived, and as he toyed with Missile Wrist, Knuckles suggested Sonic pull the old "Slap On The Wrist" trick to cause Missile Wrist to destroy one of its arms before Sonic finished the job with his Spin Attack. As Eggman retreated in disgrace, GUN forces and S.S.P.D. SWAT arrived and ordered everyone to stay where they were. Knuckles felt like they were calling him a coward and glowed with anger, but when Tails picked everyone up on the Tornado 2, Knuckles decided that the heavily-armed soldiers were not worth his time and fled with Sonic and the others, only to break off and glide away to his own intentions.

Some time later, Knuckles was approached by Eggman, who played the innocent victim and convinced Knuckles that Sonic was to blame for Knuckles being unable to return to Angel Island and resume his duties guarding the Master Emerald. Falling for it, Knuckles had Sonic face him in a one-on-one fight in the Silver Valley, only to learn then that he had been tricked by Eggman when Tails, Amy, and Chris got taken prisoner in E-47 Pumpty. Knuckles made amends with Sonic and together rescued their friends from Pumpty, while Knuckles got some payback on Eggman for tricking him.

Knuckles later showed up at Diamond Stadium when Eggman showed up with his team of E-21 Ballios to challenge Sonic and his friends to a game of baseball for the Chaos Emerald that had been found at the stadium by the groundskeeper. When Knuckles thought that playing baseball for the emerald was a waste of time, Sonic and his friends played off of Knuckles' pride and ego, taunting him into joining their team to defeat Eggman. However, while Knuckles did a pretty good job of scoring some home runs and putting Sonic's team in the lead, Eggman played dirty and had one of his Ballios attach its head to Sonic, threatening to detonate and severely injure Sonic in the process. Luckily, Knuckles was able to knock the Ballios off Sonic so it exploded harmlessly in the sky, but it gave Eggman the chance to escape with the Chaos Emerald and his remaining Ballios.

Some time later, Knuckles was near a G.U.N. installation when he saw several G.U.N. fighter jets taking off to launch an attack on Eggman's headquarters. Stowing away in the missile bay of one fighter, Knuckles had it carry him to the island where Eggman's headquarters ended up due to Chaos Control and made his way inside, meeting up with Rouge, Topaz, and a G.U.N. commando team that were sabotaging the base's generator room. However, they were spotted by Eggman's robot lackeys, Decoe and Bocoe, and locked inside. Knuckles and Rouge tried to break down the door to little success until it was smashed off its hinges by Sonic, powered up by the two Chaos Emeralds he had retrieved from Eggman. Knuckles and Rouge got into an argument before Topaz ends it by reminding them of the explosives about to detonate and they had to get out at once. They escaped onto the beach just in time before the explosives wiped out Eggman's headquarters.

Chaos Emerald Saga
Knuckles soon traveled to Oriental City to meet a friend, Hawk, whom he rescued from some ruins where Hawk believed a Chaos Emerald was located. Knuckles picked a fight with the "Bruiser Boys" in a local bar, before another man, Li Yan, agreed to take Knuckles to Hawk. However, Li Yan instead put Knuckles in the same cell Hawk is in. Knuckles soon discovered that Li Yan had a bug in the cell to eavesdrop on Hawk and Knuckles, but Knuckles waited until he was sure Li Yan was leaning in close to his radio before shouting directly into the bug from close range, knocking Li Yan out cold, and buying Hawk and Knuckles time to escape before the Bruiser Boys came to check the cell. Taking a rickshaw to an old subway station, Hawk and Knuckles headed down to the tracks where Hawk retrieved the Emerald, only to be captured by the rickshaw driver, revealed to be Eggman's E-91 Lady Ninja. The resulting battle collapsed the tunnel, but Knuckles and Hawk escaped, with the Emerald left buried in the rubble. Back at Hawk's house, Knuckles found his Shovel Claws, and used them to retrieve the Emerald, only to learn that Hawk had been kidnapped by Lady Ninja.

Meeting Lady Ninja at the rendezvous point, Knuckles surrendered the Emerald, only for Rouge to appear and attempt to steal it herself. What followed was a chase that resulted in the Lady Ninja nearly getting the Emerald from Hawk, but when Knuckles tried stopping her from escaping, Hawk soaked her with water, short-circuiting her and allowing Knuckles to deliver the finishing blow. With the Emerald in his possession, Knuckles left Hawk and Oriental City, promising to return someday. However, as he left, the Chaos Emerald gave Knuckles a vision of the Altar of the Emeralds, and a female voice giving him a cryptic message about the Chaos Emeralds, leaving him pondering over what it meant.

Later, Knuckles spotted a large beam of light coming from Filmdom City. Realizing it had to be a Chaos Emerald, Knuckles headed for the city to investigate. He arrived and met up with Sonic just as everyone was preparing for Nelson Thorndyke's plan to surprise his wife, Lindsey Thorndyke, for their wedding anniversary. However, when Nelson tripped and the ring box opened, revealing the Chaos Emerald inside that Nelson was going to present to Lindsey as his anniversary gift to her, it reacted violently to the Chaos Emeralds Sonic and Knuckles were carrying before Mister Tanaka subdued the Emerald again. Eggman soon crashed the set, literally, in the Egg Fort II, forcing Sonic, Tails, and Knuckles to deal with him, Decoe, and Bocoe. After Eggman gained possession of the Emerald, Knuckles and Sonic demanded he hand it over, but Eggman sicced E-74 Weazo on them, forcing them to deal with it while Eggman escaped with the Emerald. During the fight, Mister Tanaka attempted to protect the Thorndykes by having Weazo face him, but the robot swatted him aside easily, much to Knuckles' confusion. When Sonic found himself trapped by Weazo against a large water tank, Knuckles had him jump to safety as he broke the glass open, causing the water to spill out and extinguish Weazo's flamethrower and short-circuit it, allowing Sonic to finish the job. Though Eggman escaped with the Emerald, Sonic and Knuckles put it aside to help celebrate the Thorndykes' wedding anniversary.

Knuckles was soon asked to help stop Sonic, who had apparently gone into a non-stop running frenzy for some reason, when he popped a balloon that was carrying Sonic along via the breeze. After Sonic fell and resumed running, Knuckles tried to stop him, but could not. When Chuck Thorndyke got another idea, Knuckles assisted in setting up the trap to subdue Sonic, but when the trap could not contain Sonic and his running for an extended period, it fails, and Knuckles ends up being crushed by the trap.

However, Knuckles survived, and upon speaking with Chris later on, decided to see Eggman about forming a truce to help collect the Chaos Emeralds and induce a Chaos Control that would get them back to their home world. Though Eggman apparently agreed to help, when Knuckles and Chris brought him the five Chaos Emeralds they had collected, Eggman got word from E-77 Lucky that Lucky found the seventh one. Eggman sprung his trap, ejected Knuckles from the Egg Fort II, and took Chris hostage, before setting off to meet up with Lucky.

Furious at being double-crossed, Knuckles pursued the Egg Fort II back to Station Square, only to watch as Sonic tried to fight it after it became the E-99 Eggsterminator, but was soundly battered, bruised, and kicked into the ocean to drown. Knuckles soon broke into the cockpit to confront Eggman and demand Chris and the Chaos Emeralds back, but Rouge had already snatched them in the confusion, only for Chris to struggle and make her drop the Emeralds, before both of them were grabbed by the still out-of-control Eggsterminator. Knuckles could only watch helplessly, before Sonic reappeared, now having been transformed into Super Sonic by the Chaos Emeralds, and fought off the Eggsterminator. Super Sonic told Knuckles that his wish of going home to Angel Island was about to come true, but then told him to stay back, as Super Sonic tore the Eggsterminator apart in seconds, before unleashing a Chaos Control that brought the Mystic Ruins and Angel Island to Earth.

Chaos Saga
Thanks to Super Sonic having brought Angel Island to Earth, Knuckles was able to return to his duties of guarding the Master Emerald on the top of the ruins of the Altar of the Emeralds. However, one night, six months later, he was awoken by the sound of the Master Emerald being shattered, revealing a being of pure liquid standing in front of the gem's remains. Thinking the creature was responsible, Knuckles tried to attack it, but the creature knocked him away before disappearing. Worse, without the Master Emerald's energy to keep it aloft, Angel Island descended into the water next to the Mystic Ruins.

Knuckles soon arrived in Station Square as Sonic was facing the same creature again, now known as Chaos, where it was revealed that Eggman revived Chaos from the Master Emerald in his latest plot to take over the world. After transforming Chaos into Chaos 2 with two of the Chaos Emeralds, Eggman watched as Sonic and Knuckles fought their hardest against Chaos, and were able to emerge victorious, forcing him to collect Chaos and retreat. While Sonic and his friends searched for the Chaos Emeralds, Knuckles would search out the shards of the Master Emerald to rebuild it back on Angel Island.

Knuckles arrived later at Casinopolis, which had been cordoned off by the S.S.P.D. due to heavy damage from something large crashing into it. When Knuckles learned it could be a shard of the Master Emerald, the officers lead him inside to where the object landed. Knuckles saw it was indeed a Master Emerald shard, but when he picked it up, he had another vision of the Altar of the Emeralds in the past, where he saw the source of the voice he heard previously: Tikal, and her father Pachacamac. When the vision ended, the officers agreed to let Knuckles keep the shard, and promised to let him know if they found any more.

Knuckles continued his search before finding several more Emerald Shards, leading to him having another vision of Tikal and Pachacamac's time. Reappearing at the Altar of the Emeralds, he rebuilt the Master Emerald with the shards he had found, only to see it was still incomplete. At that point, the Master Emerald showed Knuckles an image of the Egg Carrier, as if hinting that the last of its shards were there. Knuckles was able to get a ride up there on the X Tornado with Sonic and Tails, who then revealed the X Tornado's new configuration, Battle Armor Mode, which allowed them to get a clear shot at landing on the Egg Carrier, before Tails realized that Battle Armor Mode had no landing gear, leading to a crash landing. The trio survived with minor scratches, and Knuckles went looking for the last Emerald Shards, only to have a vision of the Altar of the Emeralds in flames, before returning to the Egg Carrier, where he aided Sonic in defeating Chaos in its penultimate form, Chaos 6. Claiming Chaos' Chaos Emeralds, Knuckles returned to Angel Island to see to the restoration of the Master Emerald.

Later, Knuckles discovered Eggman lying unconscious in a clearing before being joined by Sonic and Tails. Once Eggman came to, he revealed that Chaos was still alive, had double-crossed the doctor, and sought the Chaos Emeralds for itself. After Eggman got lifted away by Decoe and Bocoe to plan his revenge on Chaos, Knuckles and Sonic were shown a final vision of the Altar of the Emeralds in the past, where they saw Chaos unleash its anger on Pachacamac and his warriors, along with Tikal pleading with the Master Emerald to stop Chaos, before being returned to the present. Chris then appeared with the last Chaos Emerald, only to be grabbed by Chaos. Sonic and Knuckles rescued him, but Chaos attained the seventh emerald and the six others Knuckles had retrieved from it, allowing it to transform into Perfect Chaos and flood Station Square.

Knuckles returned to Station Square on the X Tornado, but before Perfect Chaos could finish them off, Tikal intervened and wanted to seal Chaos back into the Master Emerald. However, Sonic rebuffed her claim, saying that it would only allow the cycle to repeat itself unless Chaos was purged of the anger and hate consuming it. Knuckles found one of the Chaos Emeralds after Perfect Chaos expunged them after draining them of their negative energy and gave it to Sonic. Sonic then used the Emeralds to transform into Super Sonic, startling Tikal; she thought the Emeralds only fed on hate and anger, but Knuckles and Tails countered that the Emeralds could be powered by positive feelings too. After Super Sonic defeated Perfect Chaos, Knuckles got worried when he saw Chaos revert back to its base form, but once it became clear that Chaos had been purged of its negative emotions, it and Tikal disappeared. Afterward, Knuckles and the others saw that Eggman had fled in the confusion.

Shadow Saga
Back on Angel Island, Knuckles discovered that the Master Emerald had been stolen by Rouge and her partner Topaz in order for Rouge to get into Eggman's inner circle. Though he managed to chase her down, Rouge still got away with the Master Emerald.

In his quest to reclaim the Master Emerald from Rogue, Knuckles traveled to the Space Colony ARK (where Rouge was) with Sonic and the others to try and stop Eggman's plot to hold the world hostage with the Eclipse Cannon. Onboard the ARK, Knuckles fought Rogue for the Master Emerald, and managed to get it back after saving her life. Though Eggman soon after tried to fire the Eclipse Cannon with all seven Chaos Emeralds inserted into it, none of them were prepared for when Eggman's attempt ended up triggering his grandfather's doomsday plan in revenge for G.U.N. killing his granddaughter Maria fifty years ago.

With the Chaos Emeralds having turned the ARK into a mega-bomb heading straight for the Earth, Knuckles realized he could use the Master Emerald to drain the Chaos Emeralds and diffuse the potential explosion. Aided by Sonic, Decoe, and Bocoe, Knuckles reached the core room where the Chaos Emeralds were, but was stopped by the Bio Lizard. Luckily, Shadow the Hedgehog arrived to distract the Bio Lizard, allowing Knuckles to perform the chant that let the Master Emerald drain the Chaos Emeralds of their power. However, the Bio Lizard then fused with the Eclipse Cannon, becoming the Final Lizard, leaving it up to Sonic and Shadow to defeat it for good in their super forms, before using a powerful Chaos Control to return the ARK to a stable orbit. When Sonic returned with only one of Shadow's Limiters, indicating Shadow sacrificed himself to stop the ARK, Knuckles took a moment to mourn for Shadow before returning to Earth with the others.

Egg Moon Saga
Sometime after the events with the ARK, Knuckles was with Rouge discussing their treatment by humanity, who were adoring them one minute, and then wanted them arrested and locked up the next. Rouge decided to tease him on this before taking her leave, offering one final remark that caused Knuckles to angrily yell back at her.

Later, Knuckles was surprised to find the newly-repaired Moon, now the Egg Moon, causing a never-ending solar eclipse. Sometime after that, during which he wondered why Sonic had gone on a rampage destroying Eggman's Mirror Towers that provided power to the Earth's Sunshine Balls, he was approached by several citizens, asking for his help to stop Sonic. Knuckles agreed and went to confront Sonic. After exchanging several blows with Sonic when they finally fought however, their fight got interrupted by the arrival of the X Tornado and Hot Shots. When Sonic revealed that Eggman was purposefully controlling the Egg Moon to profit off his Sunshine Balls and fulfill another plot to establish his Eggman Empire on Earth, Knuckles returned to the Thorndyke Mansion where, together with Rouge, Topaz, and Mister Tanaka, he traveled up to the Egg Moon in a shuttle. There, he destroyed the transmitter on the Egg Moon that was keeping it in position to block the Sun, ending the eclipse, much to his relief as he returned to Earth with Rouge and the others.

Emerl Saga
Some time later, Knuckles took part in a competition held by the President to try and lure Eggman out after he escaped prison. Knuckles finished as a runner-up in the competition before losing to Emerl, but when the latter went berserk from the energy of the Chaos Emerald that was the prize for the winner of the competition, Knuckles teamed with Sonic and Rouge to try and stop him. However, due to Emerl's ability to copy the moves of a single opponent at a time, Knuckles got overpowered. Knuckles thus had to watch as Cream and Cheese double-teamed Emerl, preventing him from using his copy ability due to their tag team tactics confusing him, resulting in his destruction.

Homebound Saga
Sometime later, Knuckles discovered the world's oldest map, which would be stolen from him by Decoe and Bocoe for Dr. Eggman. With it, Eggman planned to find the ancient continent of Murasia and through it, set off a chain reaction of volcanoes to destroy the Earth and build his Eggman Empire on the ashes of the old world. With the aid of his friends and allies, Knuckles traveled to a volcanic island with a passage to Murasia, where the they encountered Eggman, who held the passengers of the GUN destroyer Seahawk hostage. Knuckles and Sonic saved the hostages by destroying Eggman's Egg Battleship, but Eggman and his lackeys escaped to Murasia. Knuckles and co. followed Eggman down to the remnants of Murasia, but their presence triggered a chain of events that caused Murasia to be swallowed by the sea. Fortunately, Knuckles and his allies managed to escape to safety in time. Decoe and Bocoe survived after being abandoned by Eggman, and change allegiances to Knuckles and his friends.

Soon, Knuckles learned that Earth and his homeworld were merging, and if that happened, time would stop forever. As a result, Tails and Chuck created a portal that allowed Knuckles and everyone else from their world to return home. Before returning home however, Knuckles helped save the President when he was taken hostage.

Once back on Sonic's world, with no sign of Sonic, Knuckles got into an argument with Rouge, resulting in the two coming to blows with each other, until they spotted Super Sonic soar overhead, indicating Sonic was finally back. When Knuckles wisecracked about Rouge's dirtied look from their scuffle, Rouge attacked him again, but this time in a more friendly, playful fight, making Knuckles laugh.

Metarex Saga
In Season 3 after returning home, he joins the heroes gathering the Chaos Emeralds in space in order to defeat a new villainous group, the Metarex and their leader, Dark Oak. During this adventure, Knuckles had to use the Master Emerald to power up the Blue Typhoon. At first he was too stubborn to use it, but after a serious beat-down by Amy, Cream the Rabbit and Cosmo, the Master Emerald had to be used. During their final showdown, however, the Master Emerald is destroyed and drained of its power while being used against Final Mova. After this adventure, Knuckles heads back to Sonic's world and oversees the restoration of the Master Emerald, which he fails to see Chris leaving and declares war on Doctor Eggman with the others.

Early adventures
Knuckles kept the oath he took to guard the Master Emerald when he arrived on Earth. Sonic would travel to Angel Island and try and persuade him to take a break and go on an adventure with him, but Knuckles refused unless there was a good reason. Continuing his duties, Knuckles noticed a ship off the Emerald Coast and was curious watching Sonic jumping into the ocean. Suspecting that they may be a Chaos Emerald involved, he continued observing until Dr. Eggman arrived with his new Dragonbots. Knuckles helped them by rescuing Chuck Thorndyke from the ocean and was given diving gear to help Sonic, Rouge and Topaz below. They managed to destroy Eggman's Dragonbots and retrieved Captain Seamus MacGuffin's treasure, but found no Chaos Emeralds.

Knuckles joined Sonic and his friends again when he noticed missiles coming from Station Square and suspected Eggman and Sonic fighting. He came to the museum to help them fight Eggman's robots, along with Chuck, Cream and Cheese. He was instantly flirted by Rouge and told that Chris, Topaz, Sam Speed, the President and Mister Stewart were trapped inside. Knuckles worked with the others and they managed to free Chris from Eggman's control and eventually managed to free the hostages from Eggman's robots and defeat him.

Later, Knuckles would be guarding the Master Emerald when Tikal, Chaos and her army of Chao appeared from it. He would accompany them to Station Square to fight off Eggman's evil army of Dark Chao and joined the fight with Sonic, Tails and Amy. He was impressed by Tikal's fighting style being similar to his as they fought off the Dark Chao and Chaos fought against Eggman's Egg-Gantor. Chuck managed to create a device to stop Eggman's control and Sonic used this to transform the Dark Chao back to normal. With Eggman's robot defeated; Tikal, Chaos and the Chao went back to the Master Emerald and Knuckles joined Sonic and his friends to celebrate.

No Thanks for the Memories
Knuckles would be captured by Eggman and placed into virtual reality with Sonic, Amy, Tails, Rouge, Cream, Cheese and Vanilla while the machine would be powered with the Master Emerald. He would later be hit by Sonic and Amy in Spring Yard Zone as they spun to avoid a spike and thrown off a cliff with them. He blamed Sonic for getting them into this situation until they encountered a game version of Eggman. They continued through the virtual reality world eventually meeting up with the others and being flirted with Rouge until the final level. They were saved by Chris and Chuck before they were sent to the moon via Eggman's old base. Sonic took the Master Emerald to stop the launch and they all left as the base exploded. Sonic would give Knuckles back the Master Emerald once they were save. Sonic would return to Angel Island to pester Knuckles because he was bored. Knuckles would not cave into Sonic's annoyances and demanded that Sonic found someone else to bother.

Further challenges
Knuckles continued his guarding duties when "Rouge" came to Angel Island and asked if she could stay there and explained she was being set up for stealing the Moon Emerald. The fake offered to help Knuckles guard the Master Emerald, but Knuckles argued with her until he realized she was trying to knock him out and dodged her attacks. She eventually knocked him out and flew off with the Master Emerald. Knuckles would then find Topaz's office, and demanded to know where Rouge was after explaining his situation. All of them, including Captain Westwood would draw her out of hiding with the promise of the "world's largest Chaos Emerald" as a trap. At night, Knuckles spotted the real Rouge arrive and demanded the Master Emerald. They would fight and fall off the museum onto Sonic and caught by Captain westwood in a trap. Rouge managed to free them, but Knuckles tackled her into the museum only to find the imposter controlled by Eggman. Knuckles tried to take down the fake until another robot arrived and grabbed the fake Chaos Emerald. Sonic and Knuckles would work together to defeat the robot and discover the Moon Emerald and Master Emerald inside it.

Knuckles would save Sonic from Eggman's new robot on an oil rig after watching from Angel Island, but embarrassing Sonic for rescuing him. Eggman disgusted by Knuckles' appearance decided to attack both of them, starting a heated argument between Knuckles and Sonic. They began to fight off the robot, but couldn't work together, causing a realization to Sam trapped in the robot. They eventually decided to work together to stop the robot, but are worn out easily. As Eggman is about to attack them, Sam managed to work with his team and destroyed the robot. Knuckles shook hands with Sonic after the fight, and told him that he will win first and argue later "when Eggman shaves his moustache".

He was informed when Sonic disappeared after a crazy car chase and joined a search party to find him. Chris rallied them to begin the search when Sonic came back. Knuckles annoyed by his appearance was about to head back to Angel Island, but Sonic stopped him and told him who he ran into. Knuckles thanked Sonic for the information given to him about S.O.N.I.C.X. and went to find Hawk to warn him about a member of the group, Li Yan.

After this, Knuckles would later appear on television to show off his skills to Station Square with Sonic, Tails Amy, Chuck and Chris, but preferred to guard the Master Emerald. He went first and showed off his guiding, strength and climbing as Sonic was trying to show him up. After this, his skills were downloaded into Dr. Eggman's robot and was sent to attack them. He tried to take it down by himself, but was overpowered by the robot. He eventually joined Sonic, Tails and Amy to fight the robot. They managed to destroy the robot and Sonic apologized for trying to hog all of the attention. Knuckles would later hear about Sonic's charity match against El Gran Gordo and demanded that he would train Sonic to fight him. Reluctantly, Sonic agreed to Knuckles' training tactics until Knuckles was satisfied.

Green-eyed monster
Knuckles encountered Eggman and his new Greenbots when they arrived on Angel Island for the Master Emerald. Knuckles fought the robots while Eggman boasted that he only needed one more Chaos Emerald, when Sonic, Tails and Amy arrived in the X-Tornado with it. Knuckles angered by their arrival fought against the robot with the six Chaos Emeralds to stop it, but was overpowered by the others. The Greenbots managed to use the Chaos Emeralds with the Master Emerald to summon Chaos. Chaos transformed into Perfect Chaos and Eggman's green bots fused with Chaos into Chaosbot to give him full control. Knuckles went with Sonic, Tails, Amy Chris and Chuck clinging onto the Tornado to follow Perfect Chaos into Station Square. They watched as Sonic managed to obtain the Chaos Emeralds to become Super Sonic. However, when Chaosbot proved more powerful that expected, Knuckles realized that Sonic would not stay super forever while Chaos' power was limitless. Regardless, Sonic managed to stop Eggman and free Chaos who returned to the Master Emerald.

Later adventures
Knuckles would join Sonic and his friends for a barbeque and came with the Master Emerald to continue guarding it. He talked with the Chaotix about how he didn't have much excitement, but remembered his encounter with Hawk and one of Eggman's robots. The party was interrupted when Chuck called the group to a meteorite he discovered through his telescope and believed that there was a Chaos Emerald inside. Chris decided to make it a competition that they would race to bring back to the Chaos Emerald; to which Knuckles decided to be his own team, working best alone. He brought the Master Emerald with him as he travelled to the South Pole to grab the Chaos Emerald within the meteortie. He managed to grab the meteorite off Sonic, but had to choose between it and the Master Emerald when Rouge intervened. He arrived back to find Sonic there with the meteorite, but were unable to find the emerald. Chris arrived last with Charmy and Cream and had retrieved the Chaos Emerald, and thus winning the competition.

After the arrival and departure of the Prime Zone version of Shadow, Knuckles journeyed to Station Square to find Sonic after hearing of Eggman's attack, but was too late to help out.

Personality
Personality-wise, Knuckles is serious, aloof, stubborn and does not adapt easily. Headstrong and inflexible, Knuckles prefers to do things his own way which causes him to clash with others. Regardless, he is very strong-willed, seldom wavering in his determination.

Unlike the rest of Sonic's group, Knuckles walks his very own path and is able to fight many people on his own, due to his brute strength and competence at martial arts. He also never gives up once he has a goal to accomplish, especially when its about finding the Master Emerald which is his job/duty to protect it. When on a serious mission, Knuckles is extremely self-sufficient and only says a few words.

Knuckles grew up believing in honesty, and holds a strong and steadfast belief that there is good in everyone, which always lets him give people (especially Eggman) second chances. However, this makes him very naive, quite gullible and easily misled, which has given him a history of being tricked by Eggman.

Though he is cool and determined in battle and most stressfull situations, Knuckles has an extremely short temper which leads to aggression, and is difficult to talk to or reason with when he is angry. Though his wild-temper has often been known to get him into trouble, Knuckles uses his anger to fight off his enemies.

Knuckles holds a special loneliness as he is the last of his tribe of Echidnas that lived on Angel Island for generations and believes that he will never see any one like him in his lifetime. Despite of this though, he believes that he is the only person who can carry out the task of protecting the Master Emerald to ensure no one abuses its power.

Despite his solitude, temper and blunt honesty, Knuckles is quite understanding and kind, and respects those who are nice in return, but keeps to himself. However, he shows alot of empathy, especially for people he believes need some comfort. Knuckles is also extremely selfless, heroic, and valiant, willing to put his safety on the line to save people's, and even his adversaries', lives.

Physical abilities
Knuckles possesses incredibly immense physical strength. He is strong enough to hold back Sonic and Shadow's Spin Attack and could throw the Mongroun which weights 20.050 tons. When pushed to his limit, Knuckles was even able to punch through Yellow Zelkova's armor which could withstand the Sonic Power Cannon. Although not to the same extent, his lower parts possess enhanced strength too. By stretching his arms and legs outwards while airborne, Knuckles can catch the current under his dreadlock-like spines, allowing him to glide over long distances through mid-air. Also, by using the spikes on his fists, Knuckles can attach himself to walls and climb up any kind of surface with ease, no matter the material.

Knuckles is not only strong, but also happens to have great speed. He has nearly kept up with Sonic on several occasions, and is fast enough to cut large layers of land just by running in circles and avoid Shadow's Chaos Spears. Knuckles is also a proficient burrower, able to dig into any wall or floor and excels at tunneling through subterranean regions with great speed. His jumping skills are also superhuman, as he can do several high leaps across falling debris and the backs of large robots.

Knuckles is incredibly durable, resisting both Sonic and Shadow's spin dash barehanded and electrical blows without lasting effects. Also, while not significantly cunning, he was strategic enough to remove Shadow's Limiters while he struck him to weaken him.

Combat skills
Knuckles' fighting skills is a force to be reckoned with, and is said to be as fearsome to his enemies as his temper. A master of martial arts, and he mainly relies on his spiked fists to their fullest, using strong and powerful punches, such as powerpacked jabs or piercing uppercuts, to deal damaging blows to his opponents. By adding the Shovel Claws to his fists, he can enhance his punches' piercing effect.

As examples of his fighting skills, Knuckles could fight Sonic to a standstill, and even match his punches' toughness with Sonic's quick kicks. He has also defeated Rouge in a tent battle blindly, who is a trained thief and master of martial arts. In addition, Knuckles is one of the few that could defeat a Metarex commander on his own.

Miscellaneous Skills
Due to his extensive moveset, Knuckles is an expert treasure hunter and has proven himself capable of finding hidden objects in record time as seen during his many Emerald Shards hunts. Knuckles also possesses a special connection to the Master Emerald which allows him to sense and locate it, command its ability to nullify the Chaos Emeralds' power, or channel its energies for different purposes, like powering machines.

Equipment
The Shovel Claws are ancient iron claws that Knuckles discovered during his adventure with Hawk. Upon adding it to his possession, Knuckles gained the ability to burrow underground for kilometers, and break solid debris. He has also used it in combat to do sharp uppercuts.

Weaknesses
Despite his toughness, Knuckles possesses more strength than his body can handle. For example, when penetrating Yellow Zelkova's armor, Knuckles punched with such force that he partially broke his own hand.

Sonic the Hedgehog
Once he and Sonic the Hedgehog were rivals, but their differences have been resolved. Despite this, he is often jealous of Sonic's free spirit, and has an inferiority complex according to Rouge.

Sonic and Knuckles' relationship is mostly seen as a friendly rivalry, as the extent of Sonic's speed parallels that of Knuckles' strength. Sonic and Knuckles fight each other at times, but they can also be powerful teammates against fearsome foes such as Chaos, the Egg Golem and Yellow Zelkova.

Rouge the Bat
Rouge the Bat is Knuckles' rival, especially in treasure hunting. The way Knuckles can punch is just like the way Rouge can kick. The two can get into heated or playful arguments. Rouge constantly mocks Knuckles, in which he extremely dislikes in return. In the Sonic X bio, it is revealed that she has a crush on Knuckles, however it is unknown whether Knuckles returns the same feeling for her, but in a few episodes it is hinted that he may like her.

In the episode The Volcanic Venture, Knuckles and Rouge had to team up with Sonic to go into a volcano; however the two couldn't get along and were constantly arguing, but Sonic didn't mind it. But somewhere in the end of the episode Rouge flies off, Knuckles asks her where is she going; she said that she'll find Chris, Knuckles tells her to stop, he shyly smiles and says, "Hehe! Good Luck!", Rouge replies that she'll be back and comments that he is "handsome".

In episode 52, Knuckles and Rouge were simply talking to each other, until they came to a heated fight, because Knuckles was making fun of Sonic and Rouge didn't like that and said that she knows that Knuckles actually misses Sonic and he should be lucky that she came and gave him company, Knuckles couldn't admit that fact and said that she is actually the one who is missing Sonic. After brutally hitting each other, they see Super Sonic flying in the sky, they stopped fighting and Rouge asked that it is useless to fight like this, Knuckles jokingly states that Rouge looks "awful" with dirt covered on her face, Rouge then jumps on Knuckles with the camera facing the moon, and it is believed that she's tickling him (kissing him in the Japanese version), since Knuckles was heard laughing hysterically and shouting. "Rouge, stop!! That tickles!" Even if they really are fighting, it is done in a playful manner.

Doctor Eggman
Knuckles' relationship with Dr. Eggman is complex as Knuckles always seems to fall for Eggman's trickery, believing that what Eggman is saying is the best for him and it would seem that Knuckles is basically another of Eggman's mindless slave doing his dirty work without giving a second thought. Most of the time though, Knuckles is seen as a powerful threat to Eggman and his plans for world domination.

Knuckles appears to respect Eggman, despite the fact that they're enemies. This may be due to Engman generally being the villain he, Sonic and Tails are used to. However, he tends to forget about all that, once Eggman has pushed his buttons.

Christopher Thorndyke
Knuckles is seen having several friendly conversations with Chris. In episode 25, Knuckles notices Chris being nervous about being out in the woods, and he comforts him by telling him that he'll protect him. Knuckles was also the last one Chris spoke to before going home. They were seen interacting in a friendly and good-natured manner, in front of the Master Emerald, speaking about Chris's next move.

Cosmo
Knuckles and Cosmo are seen having some few interactions. Though Knuckles did not trust her at first, he develops a warm, friendly attitude towards Cosmo later on. They usually get along well, but Cosmo still joins the others in mocking him. However, Knuckles is generally protective towards Cosmo, and cares about her well-being.

Friends and allies

 * Sonic the Hedgehog (good friend and rival)
 * Miles "Tails" Prower (best friend)
 * Amy Rose (good friend)
 * Cream the Rabbit
 * Cheese
 * Chuck Thorndyke
 * Christopher Thorndyke
 * Helen
 * Cosmo
 * Shadow the Hedgehog
 * Rouge the Bat
 * Vector the Crocodile
 * Espio the Chameleon
 * Charmy Bee
 * Vanilla the Rabbit
 * Big the Cat
 * Emerl (formely)
 * Tikal
 * Hawk (great friend)
 * Doctor Cadberry
 * Topaz

Rivals

 * Sonic the Hedgehog (friendly rival)
 * Rouge the Bat
 * Emerl (after obtaining a Chaos Emerald)

Enemies

 * Dr. Eggman
 * Bocoe
 * Decoe
 * Bokkun
 * Chaos (formerly)
 * Bio Lizard
 * Metarex
 * Dark Oak
 * Pale Bayleaf
 * Black Narcissus
 * Yellow Zelkova

Trivia

 * Knuckles uses the third most amount of Engrish in the Japanese version coming right behind Eggman, who uses the second most amount of Engrish, and Sonic himself, who uses Engrish at least once in practically every episode.
 * Knuckles' mittens were drawn as gloves in "How to Catch a Hedgehog", his eyes are colored green twice in "Missile Wrist Rampage" and once in "An Enemy in Need".
 * In episode 65, Vector the Crocodile says "When I'm through with him (Knuckles), even his own mama won't notice him." Vector is probably mentioning Knuckles having a mother, thus making him possibly the second character (after Cream) to have any parents mentioned in the show although this is mainly an exaggeration.
 * Knuckles is the last friend of Chris to speak with him personally as seen in "So Long Sonic". They had their final conversation next to the Master Emerald.
 * Knuckles mentioned that he honed his fighting skills from scrolls left by his ancestors of his tribe.