What it does
Whirlwind is a status move with priority -6 that forces the target to switch out, replaced by a random Pokémon from the opponent's party. Since priority -6 means it acts last in almost every turn, the opponent's move has already fired before Whirlwind takes effect.
The switch clears all stat-stage changes on the exiting Pokémon. That's the central competitive value: anything the opponent invested into building up via Dragon Dance, Swords Dance, or Calm Mind is wiped when they leave the field. One use of Whirlwind can undo multiple turns of setup.
Fails against Suction Cups and targets under Ingrain. Only Suction Cups and Ingrain can prevent the forced switch.
Who runs it
Skarmory at 9% is the classic carrier. Its physical bulk is exceptional, and Steel/Flying typing gives it a wide resistance spread that lets it stay in long enough to click Whirlwind repeatedly across turns.
Skarmory's primary role is field control. Whirlwind is there because doubles sometimes produces setup moments — a sweeper clicks Swords Dance while a partner provides cover, and suddenly their damage is scaling out of control. Whirlwind stops that before it spirals. The high physical bulk means Skarmory absorbs physical hits while waiting for the right moment to blow the threat out.
How to use it
The core use is disrupting setup. When a setup sweeper is on the field and has boosted, fire Whirlwind to erase those boosts and swap them out for an unknown — possibly less threatening — replacement.
Priority -6 means you're not stopping the current turn. Whatever the opponent does this turn happens first. Whirlwind's value is in the aftermath: the boosts are gone, the momentum is broken, and the opponent has to rebuild from scratch with a random Pokémon they didn't choose.
The replacement is random. You can't control what comes in. That cuts both ways — sometimes you force in a Pokémon that's even more threatening for the situation. Look at the opponent's remaining team before deciding whether to fire Whirlwind or address the current threat differently.
Tips & strategy
Trick Room doesn't affect Whirlwind's timing. Trick Room reverses Speed priority, but priority -6 is an absolute floor that sits outside Speed-based ordering. Under Trick Room, slow Pokémon move first — but Whirlwind still goes last regardless.
The stat-clearing mechanic applies to the Pokémon leaving, not the one coming in. If the opponent has a pre-boosted sweeper in reserve, blowing out the current one might just invite that sweeper in. That's a calculated risk — sometimes worth it, sometimes not.
Check for Suction Cups and Ingrain before committing. Wasting a Whirlwind turn is costly — you moved last and accomplished nothing.