Moon Mirror Shield - MP16-EN039 Rare Unlimited

If the equipped monster battles your opponent's monster, during damage calculation: The equipped monster's ATK/DEF become equal to the ATK or DEF (whichever is higher) of the opponent's battling monster +100, during damage calculation only. If this face-up card is sent from the field to the GY: Pay 500 LP; place this card on either the top or bottom of your Deck.