Cannot be Normal Summoned Set. Must be Special Summoned (from your hand or GY) by shuffling 5 other Memento monsters with different names from your hand and or GY into the Deck Extra Deck. While you control no other monsters, this card can attack all monsters your opponent controls, once each. Once per turn, if your opponent activates a card or effect (except during the Damage Step): You can Special Summon 1 Memento monster from your hand or GY.