I mean, with X, not only does it gain a few weaknesses, but it also gains a crappy ability. Seriously, most mega evolutions have great abilities like Drought, Adaptability, and even Huge Power, and they give it Steadfast?! And let's not forget the fact that only the transferred Mewtwo have good physical attacks. And most mega evolutions that change type were actually given moves to accommodate a 2nd STAB. Ampharos gets Dragon Pulse, Pinsir gets Aerilate (not a move, but close enough), and Mewtwo gets nothing good. So much for using it in the next Wi-Fi tournament, where it IS allowed, but only with a blue pentagon.
And let's not forget Y's flaws. First, it gets that Defense drop, which sucks. Second, almost all of its special attacks were nerfed by 5 or 10 points. If I did the calcs right, Mewtwo Y is weaker than gen V Mewtwo. And its Attack also went up by a lot, which it doesn't even use. The only good it does is for is the opponent if they use Foul Play or Swagger.
Seriously, does anyone else agree with me? If you think you can prove me wrong, please go ahead and try.
Mega Gayrados loose water and becomes Dark, so Waterfall will be less effective~ Halectic