Whimsicott

Prankster gives Tailwind +1 priority, guaranteeing it before almost anything. Focus Sash ensures Whimsicott survives a hit to set Tailwind. Encore locks opponents into setup moves, Protect, or unfavorable attacks. Moonblast is STAB spread that threatens Dragon and Dark types.

Mental Herb cures Taunt, which is the main counter to Prankster Tailwind. Light Screen instead of Protect gives passive special damage reduction on turns when Whimsicott has done its job.