If a face-up Xyz Monster you control leaves the field due to an effect: You make all monsters your opponent controls lose 1000 ATK until the end of the turn. When your opponent activates a card effect: You can return 1 "Springans" monster you control to its owner's Deck. Then, apply 1 of the following effects.
● Negate that activated effect.
● Special Summon 1 Level 8 monster from your GY.
You can only use each effect of "Springans Interluder" once per turn.