From Emil 'HypErioN' Attlid:
The Gothisum map was an Honorable Mention in Human Head Studios' mapping contest. It is a medium-sized deathmatch ma with a quite original theme. It uses Hell.utx, but in a special way. The map takes place on a mountaintop fortress of some kind, and it's possible to go outside, and to fall down. The lighting is as dark as possible, without ruining the gameplay.