There are two dark rooms. This page will cover the normal dark room, which is accessible through the garage and the underground entrance near building B.
The dark room is entirely black, with no known methods of visibility. Night vision addons do not work, drones become disabled, console commands fail, lights dim, etc. The only method to see in the dark room is through the flashlight. There are a few puzzles that happen in it. It is also the site of numerous creepy events, like light dimming and phantom apparitions. NPCs completely break and go crazy in the dark room, dying or disappearing. There is no way to block off any entrances to the dark room. Driving a vehicle to the entrance of the dark room will explode and destroy it. Props placed inside of the Dark room will save across game sessions.
There isn't any importance to the dark room except for the few events that occur in there, and as of June 2022, the dark room only exists for those events. There are currently three puzzles.
- Grab the doll from the secret room and place it on the chair. Placing it on the chair forcibly moves the player into the big dark room, where the only way to escape is to destroy it.
- Blow up the chair when it appears. Doing so will activate the sequence that leads to spawning Ratman, and therefore spawning the map-important radio as well.
- After freeing Ratman, tuning the radio into playing the portal music and also placing it on the scorch decal in the submarine room leads to a string of numbers. Typing these numbers into the console teleports the player into the dark room, where they help Grigori fight off a few fast zombies. The command cannot be activated unless this event is done. The string of numbers is 2796-1646-20.
- There's a way to light up the Dark room. Using the command create_flashlight will make a light that looks just like the light from a flashlight, although it will persist there, even if you move.