Number C69: Heraldry Crest of Horror
Yu-Gi-Oh!
Number Complete File -Piece of Memories- - Cartas Sueltas

4 Level 5 monsters When an opponent's monster declares an attack: You can destroy all cards your opponent controls. If this card has "Number 69: Heraldry Crest" as an Xyz Material, it gains this effect. ?Once per turn: You can detach 1 Xyz Material from this card, then target 1 face-up Xyz Monster your opponent controls; this card gains ATK equal to that face-up monster's original ATK, and if it gains ATK this way, this card's name and original effect become the same as that monster. These effects last until the End Phase.