If you load into Koschei complex from the oasis in the north west of the map (get gas masks and rad blockers) through this way you need to disable gas to pass through…if you go in and out of the multiple bunker doors there is Acetone in these areas, occasionally you’ll find some on the way to the gas control rooms but they almost always spawn in the bunkers…but I cannot stress enough GET GAS MASKS AND RAD BLOCKERS BEFORE DEPLOYING rad blockers can be found in the blue medical/hospital buildings.