A robotic copy of Sonic the Hedgehog created by Dr. Eggman.
Metal Sonic is a nightmarish mechanical copy of Sonic the Hedgehog. He is capable of matching if not overcoming Sonic's top speeds. He is one of the few villains that are actually considered cold hearted (unlike others such as Shadow the hedgehog). As Neo Metal Sonic he gained the ability to copy data (abilities/traits) from other characters and also gained the ability to speak. However, despite all of his abilities, Sonic and friends always find a way to defeat him.
Metal Sonic first appeared in the Sonic CD video game and was created by Kazuyuki Hoshino who was the character designer for that game.
Sonic the Hedgehog
The Sonic OVA's combined into a hour long movie released in America by ADV Films.