Zack was born in Gongaga, where he spent his early years before he joined the forces of militant Shinra in the age of 14 and under Angeal Hewley division, for the next four years to become a member of SOLDIER.
Zack and Angeal
After the Wutai war, Zack is sent to Wutai with Angeal and Sephiroth to learn about Genesis, SOLDIER who went missing without any trace in Wutai Mission. They find that Genesis has become a traitor, and must be stopped at all costs.After the mission, Zack inherits the Buster Sword belonging to Angeal. He is assigned to Nibelheim with Sephiroth to investigate the nearby reactor Mako. They are accompanied by two soldiers, one of them is the future of friend Zack, Cloud Strife. While in the city, Sephiroth's visits Shinra Mansion and uncover documents that he misunderstood. Then lead him to believe that he is the son of Jenova, and he was the last Cetra that shown by his ability that beyond human.
Sephiroth goes mad and destroyed the city, killing most of its people. Zack went to Mako reactors and fight Sephiroth in a duel, but after a long battle, Sephiroth defeats him. Sephiroth enters the deepest part of the reactor, nearing a settlement tank contain Jenova. Suddenly, Cloud appears behind him and stabs him with Zack's Buster Sword .
Zack Vs. Sephiroth
Zack spoke with white hair Angeal and discovers that is a copy of the original Angeal. He reveals himself to be Larzard, the chief executive of the missing SOLDIER. He was injected with Angeal cells, which caused him to become a clone. Zack asked about his next move should be, and Larzard said it needed to find Genesis. Genesis hiding in a crystal cave. Genesis reveals what his real intention was, and he transforms into a giant horse. Zack defeats Genesis, and that changes in his original and battling with Zack again. After being defeated again, Genesis sees the goddess Minerva and offers his hand, but she refuses and Genesis absorbed by Lifestream. Zack out of the cave with Genesis to find Cloud and Larzard.
Larzard tells to fought against the Shinra soldiers to protect Cloud, and then he dies. Genesis Zack said that Angeal's dream has come true. Shortly thereafter, Zack finds a letter from Aerith. The letter said that it had been four years since she saw Zack, and that this is his final, eighty-ninth letter to him. Zack is confused, and he realizes that he and Cloud were in the Shinra mansion for four years. A machine to crush Shinra approaches, so that Zack escapes with Cloud, leaving Genesis behind.
In Midgar, Tseng orders Turks to find Zack before making Shinra soldiers, hoping to save them. As it nears the Wastelands, Zack and Cloud hidden preparing to fight. In the final battle, Zack was mortally wounded in the chest. Shortly thereafter, Cloud embedded outside its vegetative state, but has poisoned by Mako. He approaches Zack, Cloud pull his head in the chest, Zack gives his Buster Sword and tells him to survive. Zack then dies, and Cloud, Even with a huge burden on his heart, and later through Zack bids him farewell, and he takes the Buster Sword and walk towards Midgar, looking for work as mercenary as Zack. In the end Zack says that he "Finally be a Hero".
Final Fantasy VII
Much of Final Fantasy VII, Zack story revolves around Cloud to recover his memory, to accept his true identities rather than relying on its built "Zack" personality, and to validate himself in a world that has rejected him. When part of playable characters visits now depressed city of Gongaga, learn which is the hometown Zack. Aerith also reveals that at a time when Zack was her first boyfriend, and Cloud resembles him.
Final Fantasy VII Advent Children
Zack appears on the majority of new flashbacks throughout Advent Children. Zack's death is one of the main reasons why the cloud isolated himslef from his other friends and his feelings about the results of the fight against Kadaj and his two brothers. Zack speaks to Cloud when temporarily enters the Lifestream, saying it is not your time to die yet. Zack waves goodbye to Cloud, returning to the light with Aerith after Cloud was resurrected.
Final Fantasy VII Last Order
In a slightly different retelling, Zack and Cloud are recovered by the forces of Shinra and kept in prison. They are subjected against their will to biological experiments with genetic material from Jenova, under the supervision of Professor Hojo. Eventually, both of Zack and Cloud try to escape. Zack gives some of his clothes to Cloud and they transport to Midgar. During this time, Cloud is weak, groggy and slightly delirious. However, Zack talks continuously, which no response from Cloud, on his life and his plans to become a mercenary in Midgar and become rich. When they finally arrived outside Midgar, Shinra's security forces who have been searching for them finally catch up. They try to detain the prisoners escaped, but Zack fights to defend both Cloud and himself. Shinra troops caught with Zack and Cloud later, and Zack was killed by sniper Shinra. The troops left Cloud for dead after seeing her vegetative state. However, Cloud achieved recover. The combined weight of all these traumas finally makes brooch, and Cloud takes zack's personalities, combined with his own (this was something caused by Jenova cells therein). He believes that was a success in joining SOLDIER, and meet the role of Zack in the fateful mission in Nibelheim. Cloud took Zack Buster's Sword and go to Midgard.
Other appearance in Ehrgeiz: God Bless the Ring
Zack is a character in the PlayStation version of Ehrgeiz, functioning more or less as a boss exchange with Cloud. In the arcade, there are front and minigame events.
