Sephiroth goes back in time to change things. The time ghosts exist to keep the timeline unaltered, so whenever something happens that would change things too much, they interfere. Ex: Cloud meets Hojo too early, and Hojo tries to tell him that he's not really a Soldier, so the time ghosts kidnap him. Jessie survives, so the time ghosts trick her into grenading herself (she may live, it's unclear). The time interference causes Red XIII to see his future children and Cloud to see the aftermath of Aeris' death. Other weird, silly things like that happen.
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Not changing this sig until I decide to change this sig. Started: July 6, 2005