Yellow-Bellied Oni

[ Zombie / Effect ] When you Xyz Summon a monster: You can Special Summon this card from your hand. Once per turn: You can detach 1 Xyz Material from a monster you control, then target 1 face-up Xyz Monster on the field; reduce its Rank by 1, and if you do, it loses 300 ATK. ATK/ 1000 DEF/ 1000