Sanctum of Ugin

{T}: Add {C}.
Whenever you cast a colorless spell with mana value 7 or greater, you may sacrifice Sanctum of Ugin. If you do, search your library for a colorless creature card, reveal it, put it into your hand, then shuffle.

Battle for Zendikar Promos

Battle for Zendikar

{T}: Add {1} to your mana pool.
Whenever you cast a colorless spell with converted mana cost 7 or greater, you may sacrifice Sanctum of Ugin. If you do, search your library for a colorless creature card, reveal it, put it into your hand, then shuffle your library.