Heolstor

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.) Nightlord spells you cast have cascade.{flavor} “But eventually he awoke, crawling out from underneath the others. Though he had failed to protect anything or anyone, he yet lived. And so he cursed the world.”