Metal Sonic 7

Metal Sonic (メタルソニック , Metaru Sonikku) is Sonic the Hedgehog's robotic counterpart.

He was created by Dr. Eggman to destroy Sonic.

Metal Sonic can also perform many of Sonic's moves, including his homing attack, spin dash, and many more.

Metal Sonic is mostly on his own side ( Sonic Heroes) throughout the series except Sonic Rivals 2, where he is one of the heroic playable characters.