Hidden Ones’ Mask
This armor piece is found in Lunden.
Go to the outskirts of the northeast section of the city.
You should find some pillars built by the Romans. However, you’ll also see an odd-looking structure made of wood.
Climb on one of the pillars, clamber on the wooden poles, and jump down below.
Jump on the wooden platform and shoot the red vases in the room. This will cause an explosion that creates an opening.
Pick up the headgear and codex page inside.