If a WATER Xyz Monster is on the field: You can Special Summon this card from your hand. During your Main Phase: You can detach 1 Xyz Material from a monster you control, then you can Special Summon 1 Level 3 or 4 WATER monster from your hand or GY, but its effects are negated, also if it is used for the Xyz Summon of a WATER monster this turn, it can be treated as a Level 5 monster. You can only use each effect of "Zereort Migrator" once per turn.