this mod adds the backrooms with 19 levels when you die it teleports you to it also check the images to see everything in it
this is a list of every backrooms level it adds
level 0 level 3 level 8 level 22 level 27 level 32 level 128 level 197 level 26 level 51 level 103 level 146 level 168 The Laserscape level 4 level 990 level 0.1
also it has shops and the backrooms is 5 storys tall and more then 10 million block wide but if you tp it breaks it