Crysis 2

You will get this if you play on Veteran difficulty but I suggest playing on Supersoldier difficulty as the achievement is stackable and if you follow the guide below, it should be pretty simple.

Tip: Play through the game on the easiest difficulty first and upgrade your suit so that it drains less energy when you both run and are in Stealth mode, then start a new campaign and you will keep your suit upgrades, now run past every firefight that you possibly can.

I ran through many missions without even shooting a single shot. The video shows the only part that I had a little trouble with, but I easily beat it with this video. Good luck!

Play through the game once to get the suit fully leveled on normal or easy and then play through on veteran, Supersoldier is acceptable though, and try being as stealthy as possible, the game gets much more difficult if you never use stealth to its full potential, and really use the tactical options, they are very helpful if done correctly.

Easy to do for the first six levels. Recommended to use stealth to sneak past enemies and use alternate routes. Only kill enemies when enemies in way of objective.