Ranshi, Yarn-Spinner

Affinity for enchantments
{3}{u}{r}: The next noncreature spell you cast this turn gains "When you cast this spell, exile cards from the top of your library until you exile a noncreature, nonland card whose mana value is 1 plus this spell's mana value. You may cast that card without paying its mana cost. Then put all cards exiled this way that weren't cast on the bottom of your library in a random order."