Stealth Kragen Spawn

2 Level 4 WATER monsters Once per turn, during the Main Phase (Quick Effect): You can destroy 1 WATER monster your opponent controls. If this card, Special Summoned by the effect of a "Number" Xyz Monster, is destroyed: You can Special Summon other "Stealth Kragen" monsters from your GY, up to the number of materials this card had, then you can attach up to 1 WATER monster from your GY to each of those Special Summoned monsters as material.