It has sucker punch and sd, it'll also presumably have drain kiss making it a stronger Conkeldur with a better typing. Regular Mawile has intimidate as well meaning that mega mawiles immediate foe will have minus 1 attack.
I can see an sd set with iron head sucker punch and fairy kiss having great success.
Now the question begs to be asked: does Mega Evolution end when you switch out, and if-so, can it be reinitialized quickly? Either case, I could see situations where they could both come in handy. But if you can only Mega Evolve once per battle, stuff like Flamethrower would really pose a big threat to Mawile, because Intimidate does nothing to weaken it, and its already bad Sp. Def.
Also, stuff like Trick and Switcheroo can cripple Mega Mawile builds, since Mawile's base speed is only 50. If Trick Room isn't already in play, then we'd better hope Mega Evolution has priority.
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