mega mewtwo x

With Mewtwonite X, Mewtwo's body becomes more muscular and its eyes turn blue. It becomes a dual Psychic/Fighting-type, its physical attacks become much stronger, and its speed increases whenever it flinches.

Using Mewtwonite Y will make Mewtwo evolve into Mega Mewtwo Y instead.

This tag implicates mewtwo (learn more).