Springans Interluder

When your opponent activates a card or effect: You can return 1 "Springans" Xyz Monster you control to the Extra Deck, then apply 1 of these effects.
• Negate that activated effect.
• Special Summon 1 Level 8 monster from your GY.
If a face-up Xyz Monster you control leaves the field by card effect: You can make all monsters your opponent currently controls lose 1000 ATK, until the end of this turn (even if this card leaves the field). You can only use each effect of "Springans Interluder" once per turn.