STAR WARS Jedi Knight II: Jedi Outcast

This is story-related and cannot be missed, since it’s impossible to go through the game without killing a Stormtrooper.

This will happen right after you start the game on Mission 1 – Kejim Post. As soon as you walk around the left side of the Lambda Class Shuttle, you will see two stormtroopers to kill. As soon as you kill one of them, the trophy will pop.