>>15307225i use mmwile in a non trick room team and it does great
sucker punch fucking wrecks ghosts, play rough for dragons, pain split to recover and then another move of your choice.
foul play 1 hits aegislash after a sd, he resists play rough and suckerpunch doesn't work with shadowsneak. but it's shit against ghosts like jellicent and chandelure that you can't suckerpunch because they are using will-o-wisp. so you can pack crunch for them but aegislash might fuck you with kings shield. foul play also works great on pokemon that you don't have se on who megaevolve to raise there attack.
iron head will kill opposing fairies, fire fang for steel or stone edge for fires (though mmawile won't often survive a fire attack) or ice punch for ground types (or save that moveslot and use a flying pokemon or something with levitate)
ev train entirely hp and defence and mmawile is a crazy sweeper, he can tank anything he can't one hit and he can just painsplit on a new pokemon (because he attacks second) and suckerpunch. he CAN survive earthquake, the only things that have one hit me so far are special fire moves, flare blitz doesn't even do the trick due to such awesome defence.
tldr; mmawile is insanely good and there isn't much it can't kill. oh you sent out a megengar? 1 hit suckerpunch next turn with no atk evs while you . shit is fucking cash.