text: A while ago I found a shareware version of a DOS FPS called Alien Cabal. While being essentially a 2.5D first-person game typical of early-mid nineties, it tried to take a more realistic approach to level design, similar to Duke Nukem 3D and later games. However, Alien Cabal was released in late 1997, and this is probably the main reason why the game became obscure.