Karsus's Folly

Whenever you cast an instant or sorcery spell,
instead shuffle it into your library, then reveal
cards until you reveal a card with the same type,
cast that spell without paying its mana cost.
He aimed his spell, and choose the Goddess of Magic, Mystral. It began to unravel her, and with her, the entirety of magic. Karsus instantly knew his mistake,
had he choosn any other god, he would have accended, instead his spell nearly destroyed all of magic, and
would have if not for Mystral sacrific