Irnok, Dusksoul Feaster

Delirium — {t}: The next Vampire spell costs {2} less to cast this turn if there are four or more
card types among cards in your graveyard.
{2}, {t}, Sacrifice a creature: Return target
Scorpion creature from your graveyard to your
hand.
{3}{w}{w}, Sacrifice Irnok: Destroy all
non-Vampire, non-Scorpion creatures.