If it wasn't for the fact that I had to exclude the Chaos Emeralds from both Sonic and Mephiles, those two would be too much for their missions alone. Sonic's Super form is pretty much a 1000% boost of speed, power, and durability. Mephiles would have endless power with the Chaos Emeralds, like make an entire army of Perfect Duplicates, and that one Chaos Emerald gives him the power to summon the other six. Not to mention Mephiles has unlimited time travel abilities at will regardless of Chaos Emeralds or not.

Talk about overpowered. ><