Reminds me of Shadow the Hedgehog. Perhaps Mewtwo transforms with the Seven Chaos Emeralds?
As long as they are easier to obtain than in the early Sonic the Hedgehog games. :/ Trying to get them in Sonic the Hedgehog and Sonic the Hedgehog 2 were some of the most frustrating things I've ever had to do.
Tell me about it. Same for Sonic 4 Episode 1. Episode 2 on the other hand.... Anyways, that's just my opinion on what Mewtwo's new form looks like.
Official Co-Leader and General of Team Miror Infinity. Shadow Pokemon: Tyranitar. Feel my Plasmaaaaaa Gunblade! Also Count of "the Organization."