The Whomping Willow

{t}: Add {g}.

Channel - {1}{g}, Discard The Whomping Willow:
Destroy target artifact, enchantment, or nonbasic
land an opponent controls. That player may search
their library for a land card with a basic land type,
put it onto the battlefield, then shuffle. This
ability costs {1} less to activate for each legendary
creature you control.