Planeswalker's Mischief

3U: Target opponent reveals a card at random from his or her hand. If it’s an instant or sorcery card, remove it from the game. As long as it remains removed from the game, you may play it as though it were in your hand without paying its mana cost. If it has X in its mana cost, X is 0. At end of turn, if you haven’t played it, return it to its owner’s hand. Play this ability only any time you could play a sorcery.