Gengar

Poke-POWER: Fainting Spell

Once during your opponent's turn, if Gengar would be Knocked Out by damage from an attack, you may flip a coin. If heads, the Defending Pokémon is Knocked Out.

Shadow Room (Psychic)

Put 3 damage counters on 1 of your opponent's Pokémon. If that Pokémon has any Poké-Powers, put 6 damage counters on that Pokémon instead.

Poltergeist (Psychic, Colorless) 30x

Look at your opponent's hand. This attack does 30 damage times the number of Trainer, Supporter, and Stadium cards in your opponent's hand.