The World's Greatest Gallant Thief

If you control no monsters, you can Tribute Summon this card face-up by Tributing monsters from your hand and/or your opponent's field. You can only use each of the following effects of "The World's Greatest Gallant Thief" once per turn. When your opponent activates a card effect in the hand, GY, or banishment, while you control this Normal Summoned/Set card (Quick Effect): You can negate that effect, and if you do, destroy that card. During the Battle Phase (Quick Effect): You can reveal your entire hand; change all monsters your opponent controls to Defense Position.