Metal Sonic

Metal Sonic (メタルソニック), aka "[Sonic's] evil twin who won't stay smashed," is a robot from the Sonic the Hedgehog and Sonic Universe series. He is the evil robotic counterpart of Sonic the Hedgehog, created by Dr. Ivo "Eggman" Robotnik. As well as resembling Sonic, he can also perform many of Sonic's moves. He is noteworthy for being the second most recurring villain in the series, only below Dr. Eggman himself.

Pre-Worlds Collide
Note: This article only covers Metal Sonic's appearance in Archie Comics' Sonic the Hedgehog comic book series.

Various Metal Sonic models has appeared in the comics. Metal Sonic first appeared in Sonic the Hedgehog #25, the Sonic CD adaptation, in which he was incorrectly named Mecha Sonic. He raced Sonic as part of one of Dr. Robotnik's traps, but was destroyed at the end of the issue.

Metal Sonic returned in the adaptation of the game Knuckles' Chaotix. He was transformed into a giant red version of himself by a "Power Gem," but was destroyed by a similarly empowered Knuckles.

Metal Sonic's next appearance was in a two-part storyline. He had rebuilt himself by the power of the Power Gem embedded in him, and boasted improved powers and a new design. He captured Tails and confronted Sonic, then made him race for his friend's life to the top of a soon to erupt volcano, where Tails was tied. Despite Metal Sonic's attacks along the way, Sonic made it to the summit just as the lava began to rise. Though it seemed like they were doomed, Sonic and Tails refused to abandon one another, showing Metal Sonic that there was more to life than power. Metal Sonic held back the lava for them and Sonic and Tails managed to escape, but Metal Sonic was destroyed in the effort. (It was later discovered that this Metal Sonic's Power Gem managed to survive the lava, however, and Sonic's uncle rebuilt him, giving him a chance to prove he is a hero, and was redubbed "Shard".)

A year later, a new series of Metal Sonics was re-created from scratch by Dr. Eggman, with the first being created as part of a storyline involving a 3-way battle between himself, Shadow, and Sonic. These new Metal Sonics would from then on become fierce foes that Sonic and his allies would confront regularly.

Dr. Eggman built Metal Sonic v3.7, giving him a voice and memories of his previous versions, improving his combat abilities. He also has free will and a program to prevent him from betraying his creator like other robots, such as E-123 Omega, did in the past. His first mission is to destroy the original Metal Sonic, Shard, and although he manages to cause heavy damage to the original, he is destroyed. Shortly after the battle, Eggman creates Metal Sonic v3.8, who reports the result of the mission. Metal Sonic is eager to finish his previous mission or go after Sonic, but Eggman says he has other plans. He ordered Metal Sonic to the Interdimensional Gateway and that he will work with a "base" villain like himself. (Sonic Universe #50)

Worlds Collide
After the world is modified by the Genesis Wave, Metal Sonic was sent with Bass to kidnap Sonic's friends, starting by Miles "Tails" Prower, to transform them into the Roboticized Masters, who were more easily able to pass between worlds than Bass and Metal Sonic, who required the company of each other to pass through the worlds. (Mega Man #24)

When the Roboticized Masters stole a Chaos Emerald in Earth, Metal Sonic appeared as a blue blur to Mega Man, tricking the Blue Bomber to follow him to the Green Hill Zone and fight against Sonic the Hedgehog. (Sonic Universe #51)

During the battle, Dr. Light manages to bring Mega Man back to his world, and Dr. Wily, deducing who was the responsible, talks about Dr. Light to Dr. Eggman. To make sure he would not interfere, the evil scientists send Metal Sonic and Bass to capture Dr. Light. (Sonic the Hedgehog #248 & Mega Man #25)

Later, inside the Wily Egg, Bass and Metal Sonic chase Rouge the Bat, who was sabotaging the fortress. When cornered, she released the Chaos Devil as a distraction, but it catches her and Metal Sonic. When Eggman arrives, he orders the Chaos Devil to release them. (Sonic Universe #53)

When Dr. Light created a communicator with the remains of a Met and Motobug, Eggman ordered Metal Sonic to throw him out the Wily Egg. Later, he was ordered by the docs to guard checkpoint X alongside Bass and Treble and finish the blue heroes in case they reach the area. (Sonic the Hedgehog #250 & Mega Man #27)

Sonic and Mega Man eventually reach the area, and they battle against Metal Sonic, Bass, and Treble. During the battle, Sonic tried to attack Metal, teasing him that he beat him in every race and every fight, and even when he was "that stupid dragon-thing". However, Sonic got hit, and the two charged at each other. Due to a change in plans by the blue heroes, Mega Man ended up challenging Metal Sonic. However, the robot was too fast for Mega Man to successfully get a lock on, and the one time Mega Man did end up scoring a hit, it was absorbed by Metal Sonic's Black Shield. Metal Sonic then threw Mega Man into a box in the room. Metal Sonic then attempted to attack Sonic and Mega Man at their hiding place, but ended up embedded inside of the crate. Metal Sonic eventually got himself out, and attempted to attack Mega Man. However, Mega Man outsmarted both Metal Sonic and Treble by using Chroma Camo. After Bass was defeated, Mega Man and Sonic then proceeded to gang up on Metal Sonic: First, Mega Man used Tail Wind on Metal Sonic, then Sonic struck at Metal Sonic, with Mega Man using Sharp Knuckle on him in succession. Metal Sonic then proceeded to ram Mega Man using V. Maximum Overdrive, only for the latter to fire Rapid Stinger, with Sonic finishing Metal Sonic off with a spin dash, leaving him too injured to continue fighting. Although beaten, he alongside Bass and Treble nonetheless succeeded in wearing down Sonic and Mega Man enough to be easily captured by Wily and Eggman. (Sonic Universe #54)

Aftermath
A previously destroy version Metal Sonic was found in the Sol Zone by the Blackguard Pirates and rebuilt into Captain Metal. Captain Metal found and remodeled the Wily Egg into the Egg O' War. (Sonic Universe #55-56)

Captain Metal used the Sol Emeralds to power the Egg O' War, as well as having transferred his programming into it, which was revealed shortly as his body was destroyed. Though both are defeated when Blaze used the Emeralds herself to become Burning Blaze. The Egg O' War sunk into the ocean, but unknown to everyone else at the time is still online (due to Metal's consciousness) (Sonic Universe #58)

Trivia

 * During Sonic Universe #54, it was planned for Bass to fuse with Metal Sonic in the same way that he did with Treble, but the idea was rejected. The idea was subtly referenced in the issue's Off-Panel section, however.