Qwilfish

To fire its poison spikes, it must inflate its body by drinking over 2.6 gallons of water all at once.

Ability — Counterattack Quills: If this Pokémon is your Active Pokémon and is damaged by an opponent's attack (even if this Pokémon is Knocked Out), put 2 damage counters on the Attacking Pokémon.

Poison Sting (20): Your opponent's Active Pokémon is now Poisoned.