User blog comment:Garland's Soul/Is Mecha Sonic a forgotten Character?/@comment-115265-20110823211346

Mecha Sonic was all but disabled when Sonic was done with him.

Then, much later, Knuckles finished him off. Permanently

If we ever see Mecha Sonic again, it will be through a cameo. Or maybe a Sonic Generations boss. (We're still not clear on who's gonna be there and who isn't)

I'm quite sure Mecha Sonic is gone for good.