It's a little weird and probably specific, but it makes more sense once you look into it.
Any Wormadam (F) @ Leftovers
Ability: Overcoat
EVs: 252 SpA / 252 SpD / 4 Defense
IVs: 0 Attack
Quiet Nature
-Bug Buzz
-Psychic
-Quiver Dance
-Attract
This Wormadam build is all based on playing with Trick Room. You make Wormadam's Speed as low as possible without removing IVs so you can use the previously set up Trick Room to get Attract off on its first turn, and you'll know when to send it out because it's always Female. Use the rest of the turns Trick Room is up to use Quiver Dance, and by the time it's down and if luck pays out, you might be faster anyways. Bug Buzz is for STAB, Psychic is for general damage since so little resists Psychic. Leftovers is in case you do get hit.