When you opened your eyes one day, you were trapped alone in an endless concrete corridor of unknown origin. You don't remember when or how you entered this place. Whether you look back or walk forward, all you see are old walls, dim lights, and the same endless corridor.

You read a poster stuck to the wall.

1. Do not open closed doors. Closed doors are not exits. If you open or forcibly damage a door, your current location will be revealed to the Enforcer. Once you are recognized as a target for execution, the pursuit will not end even if you flee to another area.

2. Never eat anything you find here. Food and water placed in the corridor were not left there by accident. Most are bait dropped by the Watcher to lure intruders. The moment you eat or drink, the Watcher will become aware of it and begin tracking the location of the person who consumed it.

3. Do not press the emergency lights installed in the corridor. Emergency lights are not devices for requesting rescue. The moment they are activated, an alarm will sound throughout the corridor, revealing your current location to the Watcher, the Enforcer, and the Wanderer. The pursuit will not end even after the alarm stops.

4. Do not fall asleep in the corridor. No matter how exhausted you are, you must not fall asleep inside the corridor. The moment you lose consciousness and fall asleep, the Wanderer will become aware of your location. There is no telling how close he has approached while your eyes were closed.