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.