Metal Sonic

Metal Sonic is a evil robotic version of Sonic the Hedgehog from the Sonic the Hedgehog series, created by Dr. Eggman. As with Knuckles the Echidna and Shadow the Hedgehog, he is one of Sonic's rivals, and despite being a robotic copy of the original, he believes that he's the one that deserves to be the real Sonic. He is also very similar to Metal Mario, being a copy and rival of their respective characters.

Metal Sonic has only ever appeared in Crossover games, the first of them being Super Smash Bros. Brawl as a sticker. He later made a playable appearance in Mario & Sonic at the Olympic Winter Games.

Super Smash Bros. Brawl
Metal Sonic makes a cameo appearance in Super Smash Bros. Brawl as a collectible Sticker. Additionally, a different "Metal Sonic" appears as a playable character in Metal Brawl and as a rival in Classic Mode.

Mario & Sonic at the Olympic Winter Games
Metal Sonic's first playable appearance is in Mario & Sonic at the Olympic Winter Games. He is a Speed-type character and is naturally good in all racing events. His special skill is the Air Boost.

In the Adventure Tour of the DS version, he tries to stalk Mario & Sonic in Sparkleton and challenges them to a Rocket Ski Jumping event. If they win, Metal Sonic will let them proceed.

Mario & Sonic at the London 2012 Olympic Games
Metal Sonic returns in Mario & Sonic at the London 2012 Olympic Games, as once again a Speed-type character.

Official Profile
''Metal Sonic is new to the world of the Olympic Games. Modeled with extreme accuracy to Sonic by Dr. Eggman, Metal Sonic is one of our blue hero's earliest foes. At the Olympic Winter Games, Metal Sonic hopes to gain an advantage with his unique ability on the Wii and DS known as the Air Boost.''