Sonic is the most powerful character in Sonic.
Mephiles, Mephiles the Dark!
After all, he takes bullets, and blows to the head, and getting disintigrated like it aint no thing. He even kills sonic, can travel to any point in time and space whenever he wants, and even destroys the only thing able to stop him. If 06 was better, or made more sense, I'd honestly wonder how mephiles could have ever lost to sonic and friends
Because he fused with Solaris and sent himself back to the candle. In typical 06 fashion, Mephiles is stronger BEFORE fusing with Iblis, even though he was clearly weaker that way. Sort of like if Chaos 6 was stronger than Perfect Chaos. Also, that second Mephiles boss fight is up there with Sonic v. Silver for all time most annoying.