Research Base - Area with Rock Outcrops and Platforms in Trees

Rise of the Tomb Raider screenshot
After swinging across the branches into this area, you end up on an elevated wooden platform.

Rise of the Tomb Raider screenshot
If you wait quietly, the men below will soon run out of things to complain about and wander off in separate directions. You can then take out the 3 nearest enemies one at a time.

Rise of the Tomb Raider screenshot
Use silent headshots for the one in the middle with the ski mask...

Rise of the Tomb Raider screenshot
...and the one on the left.

Rise of the Tomb Raider screenshot
For the guy on the right, you can either use a headshot or jump over to the broken branch above him...

Rise of the Tomb Raider screenshot
...and then, when you see the Melee icon above his head, press Y/F to drop down on top of him.

Rise of the Tomb Raider screenshot
Next, head to the north side of this area, hiding in bushes along the way...

Rise of the Tomb Raider screenshot
...until you can scramble up onto a flat rock about halfway along the north edge of the clearing.

Rise of the Tomb Raider screenshot
You should be able to see the last 3 enemies from here, and if you stay back from the edge, they won't notice you. (There are plenty of other places you can hide, so by all means experiment, but this worked pretty consistently for me.)

Rise of the Tomb Raider screenshot
Wait for the man on the left to move around the side of the rock where you're standing. If he takes too long, you can shoot an arrow into the trees to draw his attention. When he's far enough from the others not to be noticed, take him down with a headshot or melee attack.

Rise of the Tomb Raider screenshot
You should be able to handle the 2 remaining enemies, but if you have the Finesse skill and want the XP bonus for chaining a sequence of stealth kills, stay hidden and use a poison arrow to kill them both at once.

Rise of the Tomb Raider screenshot
Et voilà!

[Return to the Research Base Walkthrough]