All original "Made from scratch" level with lots of lifts, triplines, stairs and doors. Designed to be a solo or cooperative level but could be edited into deathmatch without much difficulty. Purposely, dark and confusing. Lots of monsters, lots of ammo, but just enough medical & stim kits to get you through. Goes to the Military Base - Secret Level upon exiting.
Two weeks ... Probably about 15-20 hours actual time.