whenever you cast a spell, you may put it on the bottom of its owner's library. if you do, reveal cards from the top of your library until you reveal a nonland card. you may cast that card without paying its mana cost. then put all revealed cards not cast this way on the bottom of your library in a random order. this ability triggers only once each turn.
"You are safest in Candlekeep, Abdel, but I cannot keep you from the world forever."