Drannith Magistrate and Urabrask on the battlefield.
Steps
During each opponent's upkeep, Urabrask's second ability triggers, causing them to exile the top card of their library the next time they would draw a card this turn.
During the opponent's draw step, they exile the top card of their library.
Due to Drannith Magistrate, the opponent is unable to cast the card exiled by Urabrask.