Misdreavus.

Poké-PowerDark Spell

Once during your turn (before your attack), if Misdreavus is your Active Pokémon, you may flip a coin. If heads, put 1 damage counter on 1 of your opponent's Pokémon. This power can't be used if Misdreavus is affected by a Special Condition or if your other Active Pokémon is not Misdreavus.