I don't see the big deal about it if it is a new Forme, if it is you can always change it back/not use it.
Granted. I'm more worried about what this means for Smash Bros.
Although, in the Pokemon games proper, there is the question of "why screw with perfection?" Mewtwo is considered to have pretty much the ideal stat distribution (assuming for the sake of argument that simply puming up his Base Stat total, such as restoring his Special Defense to what it was before the Gen2 split, is off the table), and now that he FINALLY has a freaking signature move in combination with the ever awesome Aura Sphere, about the only thing his movepool is lacking is Nasty Plot.
...well, that and I guess they could give him some Ability that doesn't suck.
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