Ok, so this is basically an explanation to everything like why Roxas looks like Ventus, who was Xion and things like that. This whole explanation is from my friend Karuna so here goes.

As we all know in the end of Kingdom hearts 1 Sora stricks himself with the keyblade in order to free Kairi's сердце but he also released his. That was how Roxas was born but Roxas dosent look anything like Sora at all. That's because when Sora freed Kairi's сердце and his own he turned into a heartless but at the same time Ventus (from Birth by sleep) falls asleep somewhere in замок oblivion. When he does he...