megamorph

While your LP is lower than your opponent's, the equipped monster's ATK becomes double its original ATK. While your LP is higher, the equipped monster's ATK becomes half its original ATK. - Effect description.

A Spell card from Yu-Gi-Oh! with an effect to double or halving the equipped duel monster's ATK depending on the player's LP. It is often depicted as being capable of increasing the breast size of female monsters equipped by it in fanarts.