>>22801560I haven't tried it as of late... But upping Mawile's defense could be really effective with Sub-punch.
Mawile has pretty reasonable defense and great typing, so passing it something that increases substitute survivability can spell certain demise for the other side if they don't have any reasonable attackers left. (Stall teams would be particularly weak to this.)
Also passing speed to it is something not many people expect, a fast Mawile that doesn't need to rely on Sucker Punch is about as deadly as they come. +2 speed or Tailwind could mean Mawile can outspeed some common sweepers.
I imagine pairing it up with Whimsicott could be fruitful because Whimsicott is a great Prankster on its own, and when it's done for, it can let off a priority Tailwind and let Mawile come in and clean up.