I still hope it's possible to play through without a kill. Can't imagine it's that difficult to knock unconscious/subdue someone until the authorities arrive. In the beginning the devs mentioned you could do it and recently someone mentioned, it's no longer possible.
It always struck me as odd, there was never enough Tranquilizer darts in vanilla Deus Ex to complete the game. Would have been nice to boost the damage with a aug/skill to make it useable in end game.
In the future, it's only possible to kill people, not stun them.
Scorpio Slasher: ... What about you boy, what do hate?
Marcus: ... Bullies. Tiny d*ck egotists who hurt people for no reason, make people lock their doors at night. People who make general existence worse, people like you.