Mewtwo definitely doesn't have nothing. He may not have much, but what he does have is good. Shadow Ball is a great projectile with big damage, knockback, and shield damage. D-tilt sets up very nicely, jab sets up for a grab, Disable isn't as hard to land as it seems, and obviously Shadow Claw is great. Dash attack is good, and back air is alright for edge guarding. His recovery is one of the best in the game. His neutral is terrible, though. I usually just tomahawk until they approach, then I either Shadow Claw or D-tilt. He's not as bad as most people think, but really, none of the low tiers are, so it's definitely reasonable to say this game is balanced/fair, just not as much as 64, when all twelve characters basically have 0-deaths on every other character.