The Chronicles of Riddick: Assault on Dark Athena

This achievement is going to be easiest on the Easy difficult, but is not necessary as I personally got it on Normal.

After jumping down the air duct and opening all prison cells, you'll find yourself locked in a drone control room. Jump in one of the control units. An important thing to remember here is that at minimum you must use 2 drones for this challenge, so you must more or less be perfect.

While controlling the drone, you'll need to walk forward until you see a fan behind a grating. Shoot the lock at the top of the flashing piece and it will fall open. Walk the drone forward into the fan. You'll see a quick cutscene and the drone will be destroyed, first drone dead. Hit Y again to access a second drone. Go back to the same place and walk through the now stopped fan.

Around the corner to the left, several mercs will be waiting in ambush. To get the achievement, all of these mercs have to be killed without you accessing another drone. Try aiming for the head as much as possible As soon as the last merc drops, your achievement should unlock.

It should be worth mentioning that as soon as the last merc is dead, several more drones will activate and will likely destroy the drone you are using. It shouldn't matter though as you should already have the achievement.