Target 1 face-up Xyz Monster your opponent controls that has Xyz Material; detach all Xyz Materials from it, and if you do, return it to the Extra Deck, then, if there is a Monster Card in the Graveyard among those detached Xyz Materials, Special Summon as many of those monsters as possible from the Graveyard to your opponent s side of the field in face-up Defense Position. Their Levels are reduced by 1 on the field. Cards and effects cannot be activated in response to this card s activation.