Metal Sonic

 is a metalic version of Sonic created by Dr. Ivo (the Eggman) Robotnik, with the idea of fighting fire with more fire in mind. This metal Sonic is the second version created, as well as the most commonly used in the video games.

In M.U.G.E.N, has been made by several authors, but the most notable ones are SuperMystery's version and MugenHunter's version.

SuperMystery's Version
Surprisingly enough, SuperMystery's version plays more like a playable Sonic character than a Fighting Game Character, or even a boss-fight. As such, Metal Sonic has similar gameplay to SuperMystery's Sonic, Tails, Knuckles, Espio, and Vector, utilizing many of the same power-up monitors as well.

MugenHunter's Version
MugenHunter's version, also known as Metallix, is the boss character of MugenHunter's first Freedom Fighters. He carries moves based on all of the playable characters, as well as a few of his own moves thrown into the mix, such as his laser beams and electric shield.

Txpot's version
Another note-worthy Metal Sonic Mugen character was made by Txpot. While decent, Txpot's version is rather inconventional in terms of his moves.