Zu is an enemy in Final Fantasy IV: The After Years. It is a rather powerful enemy that can attack twice in one turn, and will take a while to bring down due to its massive HP at the time it is first fought. Using bows is the most effective way of combating this creature.
In Edge's Tale, Izayoi must fight a Zu alone as a boss. It's best to have Izayoi in the back row equipped with a bow and arrow, to avoid taking heavy physical damage from the birds double attack. While the Zu is indeed powerful, it is also slow, so there will be time to heal after its attack using Heal pill, and to attack again. The player should have little problem if they prepare this way.
Anzû, before misread as Zû, is a lesser divinity or monster in several Mesopotamian religions. He was conceived by the pure waters of the Apsu and the wide Earth, or as son of Siris. Anzû was seen as a massive bird who can breathe fire and water, although Anzû is alternately seen as a lion-headed eagle (like a reverse griffin).Zu means "fire" in the Sumerian language.