Deus Ex: Human Revolution

Should come with ease if working on a stealth playthrough. Throughout the game just use non-lethal weapons and takedowns.

Non-lethal weapons include, Stun Gun, P.E.P.S., Tranquilizer Rifle, gas mines and gas grenades.

For non-lethal takedowns walk up to an enemy(preferably behind them since they are quite trigger happy) and press B, but DON'T HOLD B. If you hold B you'll kill the target.

To confirm they are knocked out just look at the body and if you see "Zzz" instead of the skull it means they are unconscious.

Repeat 100 times on enemies(no civilians) and it's yours.

Warning contains spoilers!

If your don't already have this through the storyline during the last mission there are a ton of "zombies" easiest way to put them as they are just mindless husks wandering about that will attack you but count as enemies, during the previous mission I recommend stocking up on gas grenades P.E.P's and stun gun ammo and then just go through the mission as you would normally stunning all of the crazy people.

When using the Tranquilizer rifle, head-shots work best on the heavies (Enemies with heavier weaponry/full face helmets), as sometimes a body shot wont register or will take longer then what you want (as most of the time you want to time when they fall). Be careful, if you miss, some enemies will hear the actual tranq dart zoom by/ricochet.

The stun gun has very limited range, best for when low on energy/ or you don't want to expose yourself. Also, not many know this but the stun gun can temporarily disable cameras! Roughly seven to ten seconds.

The P.E.P.S. (rifle?) is a very loud non-lethal weapon, and very stodgy when it comes to hit detection, use carefully.

Lastly, (I say this because I did not know this) gas mines can be created when inserting a gas grenade into a mine template. Works wonders in Hengsha, esp in TYM.


PS, If you knock out an enemy and do not hide/clear the area, other enemies can revive him, of-course if you are lazy/evil just place a gas mine on the body.

On the Panchaea mission after breaking the lockdown, there are tons of crazed workers wandering around. I was quite a ways from having 100 and I bet I got 30-40 from these guys. One thing that makes it easy to get a lot of them is they can't get over any obstacle. On one section, there are probably 25 or more and at the very beginning of the area is a stack of some building material. I would jump over, knock one out and jump back across so they couldn't get me. Then wait for your energy to recharge, punch another, jump to safety, etc.

You should unlock this achievement if you're trying a Pacifist run. But be wary, sometimes a skull can be shown when highlighting a body, but it will still count for the Pacifist achievement if you had the 'Merciful Soul' XP bonus popping.

Update 29-01-2016: Fixed a typo.