The Darkness is a mod designed to put the players into a much more difficult position than that of the original Alien Swarm, by removing a lot of lighting, as well as adding support for 8 player cooperative games, both Online and Offline with bot support. Aliens burn in the light from flares, medpacks and buff mines, ala Pitch Black (Riddick), and of course the Bloodhound transport lights also have the same effect. The end goal is create a seperate version of Alien Swarm for the Riddick's among us. Enjoy! Development is in progress, and a working BETA is available.
SwarmTactics 0.5 readme (also includes The Darkness 0.5 in this version)