Narrakka, Wild Mage

0: Each player sacrifices a creature. (Whenever you sacrifice a creature, put a loyalty counter on Narrakka, Wild Mage. )
-3: Reveal cards from the top of your library until you reveal a creature or planeswalker. Put it onto the battlefield. Put the rest into the grave.
-X: Put any number of target creatures with total mana value X or less onto the battlefield under your control.