Zack Fair Biography
As it turns out, Zack only looks like a minor background character. In fact, he has a bigger role in Final Fantasy VII than it ever seemed like he might, although some of his importance was grafted on after the fact.
Like his eventual comrade Cloud Strife, who he physically resembles somewhat (except for his brown hair), Zack left his home in a small town to join the Shinra Corporation’s elite SOLDIER force. He succeeded in that immediate goal, becoming a respected member of the unit and helping train future recruits, including Cloud.
The two of them had the misfortune of being part of the unit sent to Nibelheim, however, and both were victims of their commander Sephiroth’s rampage throughout the town. Badly wounded by their encounters with Sephiroth, they were easy prey for the mad Shinra scientist Hojo, who used them as fodder for his genetic experiments until they were able to escape. It was in the process of their ordeal together that Cloud, his mind disordered by Hojo’s manipulations, took on some memories and characteristics borrowed from his comrade.
In his younger days, Zack was a good friend of Aerith Gainsborough, a young flower-seller in the slums of Midgar. In retrospect, perhaps his resemblance to Zack is part of what initially drew her to Cloud.