Harvest Hound

Landfall - Whenever a land enters under your control, you may sacrifice a land you control to search your library for a basic land and place it into your hand. (Do this only once per turn.)

Revert {g} or {u} - If this is a creature, when it dies return it to battlefield as a land. This reverted land loses all abilities except
{t}: Add {g} or {u}.

"The crop dies only to feed the next rotation."