Power Wall

Card type	Monster
Attribute	TRAP"TRAP" is not in the list (DARK, DIVINE, EARTH, FIRE, LIGHT, WATER, WIND, ?, ???, THUNDER, ...) of allowed values for the "Attribute" property.
Activate only when an opponent's monster declares an attack. Send any number of cards from the top of your Deck to the Graveyard. Decrease the amount of Battle Damage by 100 for each card you sent to the Graveyard by this effect.

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