Qwilfish

The small spikes covering its body developed from scales. They inject a toxin that causes fainting.

Ability — Bursting Needles: If this Pokémon is in the Active Spot and is Knocked Out by damage from an attack from your opponent's Pokémon, put 6 damage counters on the Attacking Pokémon.

Poison Jab (30): Your opponent's Active Pokémon is now Poisoned.