Metal Sonic

Sonic CD (1993)
Metal Sonic was created by Dr. Ivo Robotnik shortly before the events of the game as a copy of Sonic the Hedgehog. Like his original, Metal Sonic had incredible speed and strength, but also the benefits of the robotic form, such as new attacks or flight. The goal of creating Metal Sonic was to defeat the real Sonic in a race. Sometime after the creation of Metal Sonic, Dr. Robotnik chains up the Little Planet, a mysterious formation inhabited mostly by plants and over which time has no power. Using the power of Time Stones, Dr. Robotnik returns to the past of the Little Planet and takes it over. Soon after, Sonic arrives at the Little Planet to stop the villain. He is pursued by Amy Rose, a pink hedgehog and a big Sonic fan. Once on the Little Planet, Amy finds Sonic, but he shows no interest in her until she is kidnapped by Metal Sonic. Sonic chases his metal replica while also collecting Time Stones and destroying the robot-producing machines of the past. Metal Sonic challenges Sonic to a race, but loses it completely. After winning the race against Metal Sonic, Sonic saves Amy from captivity and after defeating Dr. Robotnik they leave the mysterious place.

Sonic the Hedgeog 2 (1992)
Robotnik created a new version of Metal Sonic – Mecha Sonic. Apparently, it was an entirely new robot and its functionality was significantly less than the original Metal Sonic – Mecha Sonic, while much better protected, was much slower and clumsier, which led to his natural destruction by Sonic.

Sonic the Hedgeog 3 & Knuckles (1994)
Robotnik improves the original Metal Sonic to a new form, Neo Metal Sonic. Neo Metal Sonic, unlike Mecha Sonic, is a big step forward. Not only was Neo Metal Sonic capable of driving any vehicle, but he was also faster, more aggressive, and had extremely powerful attacks. This iteration also began to possess its own senses and intellect, which were just as villainous as those of its creator. However, even after all these improvements, Neo Metal Sonic was still defeated by Sonic and his best friend Miles “Tails” Prower. However, after his own defeat, Neo Metal Sonic did not give up and took advantage of the fact that one of Dr. Robotnik’s robots called Egg Robo managed to steal the powerful jewel Master Emerald from its guardian Knuckles the Echidna and put his hands on the artifact, taking some kind of Super Form. Knuckles faced Super Neo Metal Sonic in battle and defeated the robot, returning the Master Emerald to the altar.

Knuckles’ Chaotix (1995)
Dr. Robotnik is in the process of completing his plan by capturing Newtrogic High Zone and powering up his robots with Dark Rings. Knuckles along with Espio the Chameleon, Mighty the Armadillo, Vector the Crocodile, Charmy Bee and robots Heavy and Bomb stood against the villain and made a number of attacks on Robotnik’s bases, causing this to provoke Robotnik into using his strongest robot – Metal Sonic, (who returned to his default form somehow). After the defeat of Metal Sonic by the heroes, Robotnik decides to put everything on the line and strengthens Metal Sonic with the Dark Ring, which makes Metal Sonic take the form of the incredibly powerful robot Metal Sonic Kai. However, even with the power of the Dark Ring, Metal Sonic Kai is defeated by the heroes and Dr. Robotnik’s plan is stopped. 

Sonic Heroes (2003)
Neo Metal Sonic (who again changed his version from default one to the empowered) decides to avenge defeat by Sonic’s hands by capturing Eggman’s Empire and all its robots. Neo Metal Sonic takes Dr. Robotnik (who took the nickname “Dr. Eggman” for himself) as a prisoner and takes Eggman’s form himself thanks to his newfound ability to change his form. Shape-shifting was not the only new ability of Neo Metal Sonic, as in addition, he was also able to copy the very DNA of living beings. Thus, Neo Metal Sonic copies Eggman himself almost completely, making him virtually indistinguishable from the Doctor. Similarly, by provoking Team Sonic to fight Eggman’s fleet, Neo Metal Sonic copies Sonic’s speed, Knuckles’ strength and Tails’ flight speed. By kidnapping Froggy and Chao Chocola, Neo Metal Sonic also manages to copy the DNA of the god of destruction, Chaos himself. Similarly, taking advantage of Team Dark’s search for Dr. Eggman for their own purposes, Neo Metal Sonic was able to copy the DNA of the Ultimate Life Form named Shadow the Hedgehog. After all these preparations, Neo Metal Sonic gained unmatchable power and managed to take the form of Metal Madness, becoming the lord of all robots. Metal Madness was completely invulnerable, so it was nearly impossible to defeat him. However, while Team Dark, Team Chaotix and Team Rose distracted Metal Madness, Team Sonic managed to take Super forms with the power of 7 Chaos Emeralds. Metal Madness also completes his transformation by becoming Metal Overlord. Thus, Metal Overlord and Super Team Sonic collide in an incredible battle, resulting in Metal Overlord’s defeat. Metal Sonic asks Sonic why he can’t win, to which Sonic replies that it’s because the heroes worked as a team. After Metal Sonic turns off, he is picked up by E-123 Omega and Shadow, whereupon, apparently, Metal Sonic is returned to Eggman. After these events, Dr. Robotnik realized it was dangerous to leave Metal Sonic with emotions and deprived the robot of that privilege. 

Sonic Rivals (2006)
A mysterious alien from the future named Eggman Nega arrives in Sonic’s world with a special powerful artifact in the form of a camera capable of turning objects and even living creatures into cards. Using this camera, Eggman Nega captures Eggman and turns him into a card. Metal Sonic supports Eggman Nega in his plans, though it’s hard to tell if this is the same Metal Sonic that previously served Eggman or a different version of Metal Sonic created by Eggman Nega. If it is the original, again, it’s hard to say why it serves Eggman Nega – whether because he is unable to tell Eggman and Eggman Nega apart or because Eggman Nega has reprogrammed him. Either way, Metal Sonic, undaunted by his ability to copy enemy abilities, faces off against Sonic, Knuckles, Shadow, and as well as a guest from the future named Silver the Hedgehog, who has come in pursuit of Eggman Nega in several races. However, Metal Sonic lost all of his races, and Eggman Nega was defeated in the end by the heroes, who were working with Dr. Eggman. Eggman was also released from the card by Shadow. 

Sonic Rivals 2 (2007)
Eggman Nega again invades Sonic’s world with another villainous plan. He wants to open a portal into the dimension of the powerful Ifrit monster and feed the monster with live Chao to release it into the world. From Gerald Robotnik’s diary Dr. Eggman learns that 7 Chaos Emeralds are needed to open the portal, so Eggman sends Metal Sonic to Shadow and asks the hedgehog for help in finding the Emeralds. Shadow and Metal Sonic, working together, build a rather friendly, trusting relationship, which hints that Metal Sonic hasn’t lost all emotion after all. The duo also encounters a version of Metal Sonic created by Eggman Nega, Metal Sonic 3.0. Against all odds, Metal Sonic, along with Shadow, defeats Metal Sonic 3.0, Eggman Nega and even Ifrit himself, but finds themselves trapped in Ifrit’s dimension. Shadow is trying to figure out how to get out when suddenly, Metal Sonic destroys himself by extracting the Chaos Emerald from his body. Using the Emerald’s power, Shadow applies Chaos Control and teleports himself and Metal Sonic back to their home dimension.

Sonic Free Riders (2010)
Shadow decides to help his friend, a thief named Rouge the Bat to win a world Race Grand Prix, but to join it they needed a third member, so they took a random robot of Eggmans, which was E-10000B. After winning a Grand Prix and waiting for a prize, E-10000B suddenly exploded and from its shell Metal Sonic appeared. All this time while the races Metal Sonic was collecting the racers data to defeat Sonic in a race, but in the end, even with all that data, Metal Sonic failed in a race with Sonic. 

Team Sonic Racing (2019)
Dr. Eggman creates another villainous plan. Joining Team Eggman with Metal Sonic and Zavok (leader of the Zeti), Eggman infiltrates the races organized by Dodon Pa, the president of Donpa Motors. Getting close enough, Eggman kidnaps Dodon Pa in order to steal the Ultimate Energy Engine created by the president from the Team Energy he extracts from the races. Eggman manages to use the Engine to create the ultimate machine, the Death Egg. Even with its power and the help of Metal Sonic and Zavok, the villains fail to defeat Sonic (along with the other heroes) and Dodon Pa is rescued from captivity.