(Grass-Crater isn't a spell.)

Grass-Crater enters the battlefield tapped unless you reveal an Ape Dwarf card from your hand.

Grass-Crater is indestructible. (Destroy effects and lethal damage don't destroy it.)

, Pay 1 life, Sacrifice Grass-Crater: Search your library for a Mountain or Forest card and put it onto the battlefield, then shuffle your library.