Who killed zack?

Well, after the whole 'Neblheim incident' (Sephiroth going crazy, destroying the town and Cloud eventually killing him), Zack and Cloud were put in a lab for several years and injected with high levels of Mako. Zack, being used to the level of Mako as he was in SOLDIER was able to escape his test tube and rescue Cloud, who had not been exposed before hand and was catonic. Soon after escaping, Zack and Cloud began to be pursude by the ShinRa army (though Zack never found out why). Eventually, they reached the cliff right outside of Midgar (the place were the movie Advent Children first shows Cloud) and many members of the army are there. Zackk manages to defeat a large portion of them but is eventually shot muliple times in the chest by a grunt. Soon after, Cloud wakes out of his coma and struggles to kneel next to Zack and is given the Buster Sword the told to 'Live for the both of us. You are my living legacy.' Zack dies of blood loss and multiple bullet wounds to the chest. I hope this helped.

:'(

-flyintoyourarms

Zack tryied fought the shinra army but got Shot so many times i lost count anyway zack killed most of them and just about to recover when who else but 3 shinra captains come up and finish the job by poping a shell in zacks head and eventaly dies by blood loss and names cloud his living succeer when cloud drags himself to zack and then the end