Officiating Reverie

If this card is in your hand: You can discard 1 other card; Special Summon this card. If an Xyz Monster(s) is sent to the GY, while this card is in your GY (except during the Damage Step): You can banish this card; Special Summon 1 Zombie monster from your GY. During the Standby Phase of the next turn after this card was banished: You can target 1 Zombie Xyz Monster you control; attach this banished card to it. You can only use each effect of "Officiating Reverie" once per turn.