Gengar

On the night of a full moon, if shadows move on their own and laugh, it must be Gengar's doing.

Ability — Life Shaker: As often as you like during your turn, you may move 1 damage counter from 1 of your {P} Pokémon to another of your {P} Pokémon.

Hypnoblast (90): Your opponent's Active Pokémon is now Asleep.