Chase, Underworld Enforcer

At the beginning of each player's end step that player reveals the top card of their library. If that card is an instant or sorcery you may have them put that card into their graveyard. If they do not put a card into their graveyard this way, they may put that card on the top or bottom of their library instead. During your turn you may cast instant or sorcery spells from any player's graveyard, using mana of any color to pay for that spell. If a spell cast this way would be put into a graveyard, exile it