Haunt of the Black Willow

This spell costs {1} less for each creature in your haunteds. (Your haunteds consists
of up to one each of Zombie, Vampire, Werewolf, and
Spirit.)

{1}{b}{t}: Look at the top three cards of your
library. You may reveal a Zombie, Vampire,
Spirit, or Werewolf from among them and put it into your hand. You lose 1 life.