A single player adventure based on a Doom 2 map I did last year called "Claustrophobia". Not as dark or as cramped as that original since there isn't as much control over the environment. I really worked on atmosphere and gameplay in this one. There is one checkpoint. It is a VERY active environment and should keep you busy right to the end. If you find the time after a battle, take a look around. I did alot of things with placement of FX that should make this map much more interesting than the average map.