Cage of Nightmares

■ Set

■ The abilities of this card on the field cannot be nullified.

■ When a 《Black Dragon》 monster enters your field, put the top card of your opponent's deck into his or her drop zone. This ability only activates once per turn.

■ When this card is put into the drop zone from the field, put up to one 《Black Dragon》 monster from your drop zone into your hand.