Gengar

You can hear tales told all over the world about how Gengar will pay a visit to children who are naughty.

Ability — Shadow Pain: When you play this Pokémon from your hand to evolve 1 of your Pokémon during your turn, you may put 6 damage counters on your opponent’s Pokémon-GX and Pokémon-EX in any way you like.

Twilight Poison (70): Your opponent’s Active Pokémon is now Asleep and Poisoned.