Uagadou School of Magic

{t}: Add {u}.

Channel — {3}{u}, Discard Uagadou School of Magic: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

...visitors speak of a stunning edifice carved out of
the mountainside and shrouded in mist, so that it sometimes appears simply to float in mid-air.