WarGreymon is a mega level Digimon that is very powerfull, one of the strongest Digimon ever. It's impossible for any level of Digimon to defeat it besides other Mega Digimon. It usually digivolves from MetalGreymon and it could digivolve into the even more powerful Omnimon (which is still considered an Mega) if he's DNA digivovled with MetalGarurumon.