Kill them all. Go loud from the start.
- Start with the 2 at the back of the tunnel behind you.
- Many will stream into the tunnel entrance, making them easy targets.
- When you go left towards the platform with the turret and and another couple of enemies, go to the back of that short tunnel first. There are two sleeping soldiers you must kill, and keys to a safe. Enter the doorway at the back of the tunnel, turn off the power, and head down to get 150 rounds from the safe and a nicely set up weapon.
- Make your way across the bridge, killing everything. Throw a flame grenade at the vehicle when it arrives. When you reach the other side, be sure to check downstairs under the bridge for another soldier or two.
- At the end of the bridge, head downstairs to find the prisoners about to be executed. In one run I let the guy kill them and did not get the trophy. On my second run I threw a grenade in to kill them all myself, and that worked. It should be possible to get Rescue Ranger at the same time. You cannot kill them after they have been rescued so you must reload checkpoint.
- In the final area, you can stay at the tunnel entrance and they will all come to you. Upon killing the last one, the trophy should come right away. In the train down from the tunnel entrance there are safe keys at the front and 150 rounds in the safe at the back.