SCRAR is a prototype Metal Sonic from around Sonic 1, but was locked away in Scrap Brain Zone for being too powerful.
SCRAR looks like Metal Sonic, but severely damaged with metal wires sticking out of him and one eye broken. His shoes are also unpainted.
SCRAR was built sometime during Sonic 1, but after being deemed too smart, he was locked away in Scrap Brain Zone, where he lives to this day. He has witnessed most of the times Sonic defeated Eggman [except for Sonic Rush, Sonic Rush Adventure, Sonic Generations and Sonic Chronicles] and knows how not to lose a battle.
SCRAR had no abilities by the time he was scrapped, but he can use weapons and take advantage of some of the area. He is also a bit slow.
SCRAR can use most of the machines from Sonic 1, as they were all stationed in Scrap Brain Zone for years and he gradually learned how to use them.