The Airlock (2)

Start by picking up the fresh Gas Mask, ammo, and a Kalash from a dead guard near the tunnel exit.

Move right around ice blocks to find a filter and throwing knife in a shed. The scattered ground corpses have no loot.

Proceed to the far right and climb the ladder. Turn off the lamp and hide behind the boxes on the right.

Deal with the three soldiers on the catwalks. Stealthily take out the two on the main platform.

Grab the NOTE from the box by the ladder, along with a Tikhar and supplies.

If the third catwalk soldier becomes suspicious, move down the right wall and hide behind a box. Take him out when he approaches.

Instead of the direct path to the surface via the guard post stairs, take a more detailed route.

Continue along the wall to find a Helsing near a body by the spotlight.

The ramp on the airlock side leads to stairs to the surface guard post. Alternatively, use boards on the ladder side to reach a depression on the surface. A Medkit is near a body there.

Follow wooden boards to reach girders and pipes above the airlock.

These lead to a platform with a small case containing sticky grenades. A filter can be found behind sandbags near a skeleton to the left.

To the right, access the left side of the guard shack.

Go around the corner of the guard shack and disarm the wire trap.

Continue around the corner and stealthily eliminate the guard outside the building.

Enter the building and eliminate the guard inside. This guard drops a filter, and more filters and ball bearing ammo are on boxes inside.

Exit the building and head towards the large building on the left. A demon will carry off a soldier.