The Backrooms
The Backrooms is a hellish dimension, located outside of the known Universe. You have a VERY, VERY high chance of dying. I don't care what you do; you're most likely not going to make it out. Maybe, if you have been blessed by all of the Gods at once.
Conspiracy Theories
According to theorists, Adolf Hitler may have escaped to the Backrooms, to where he lives in this day. We think. There has been MANY theories about fathers, mothers, laundry, food and many other things. If you shout out, 'I want to meet my father,' you will have a 0.005% chance of teleporting to Level 0.
Entrance
To enter The Backrooms, one has to slip out of reality. There are a multitude of ways to perform this feat, such as hitting on one's head with a baseball bat seven or eight times or smashing oneself against a wall. Even the most unsuspecting thing can take you to The Backrooms if you're not wary enough...