Rogue Trooper Redux
33 Achievements
GOG
Didn't See That One Coming
Accumulate 100 Headshots in any game mode. Details for this achievement will be revealed once unlocked
22.8%
How to unlock the Didn't See That One Coming achievement in Rogue Trooper Redux - Definitive Guide
A very quick boosting method is on mission 3 Nort Naval Base right at the start of the level as you load in there is an enemy who you can snipe for a head shot and another just to the left of him for a second. simply reload the checkpoint and rinse and repeat. here is a video I made of me showing this process.
See Pin Point Accuracy for details on how to obtain this trophy.