So i have played this map alot and I am going to tell u some things I found in it. First one is at a building called Cafe Baltic from Half life 2. If you press E on the door you will hear a combine stalker scream from HL2. Next one I will tell you where it is,it is at the far side of the map at the direction of the citadel. If you go near it you can hear a EVIL version Grigories laugh. This one scared me alot. Next one I was NoClipping and I found a admin room. When I enter I heard a LOUD scream. Last one happened on a night version of this map. I was playing And This creepy dog was following me. It might have been a mod I downloaded. Bye and you are welcome for the warnings.