Boseiju, Who Endures

{t}: add {g}.
Channel-{1}{g}, Discard Boseiju, Who Endures:
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.