Detritivore

Detritivore's power and toughness are each equal to the number of nonbasic land cards in your opponents' graveyards.

Suspend X—X3R. X can't be 0. (Rather than cast this card from your hand, you may pay X3R 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.