Ariados

It attaches silk to its prey and sets it free. Later, it tracks the silk to the prey and its friends.

Ability — Poisonous Nest: Once during your turn (before your attack), you may use this Ability. Both Active Pokémon (except for Grass Pokémon) are now Poisoned.

Impound (30): The Defending Pokémon can't retreat during your opponent's next turn.