User blog comment:SethRollinsBabyFace/Who do you think It's Final Boss?/@comment-26441687-20160313141447

Considering there is supposed to be different endings planned with different final bosses, there's no one answer to that. My theory is that you would be able to side with a certain faction, taking up their plan for saving the world and thus the final boss you face depends on who opposes that plan.

I would also like to see a 'true' end sort of deal where every joins together to fight against some deus ex machina kind of villain that fixes everything when it's defeated.