Acid does damage and has a 10% chance of lowering the target's Defense by one stage.
In Stadium, Acid has a 33.2% chance of lowering the target's Defense.
Generation III[]
Acid will hit both opponents in a Double Battle.
Generation IV onwards[]
Acid now has a 10% chance to lower the target's Special Defense by one stage instead of Defense. In Triple Battles, Acid will only hit opposing adjacent Pokémon.
Learnset[]
By leveling up[]
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