There are 12 endings - 3 different narrations for each of the 4 choices... What exactly changes this?
Killing enemies? How many do you need to kill to get the neutral ending? What about "innocents"? Notable NPCs?
How do the quests factor into this (saving people, defusing the bomb near the start)? Dialogue? Does being an a****** factor into this?
I already got the good narrations, so you can drop spoilers here and there.