Detritivore

Oracle text

Detritivore's power and toughness are each equal to the number of nonbasic land cards in your opponents' graveyards. Suspend X—{X}{3}{R}. X can't be 0. (Rather than cast this card from your hand, you may pay {X}{3}{R} and exile it with X time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.) Whenever a time counter is removed from this card while it's exiled, destroy target nonbasic land.