More often than not, letting go is unfortunately the name of the game in the modding community. Most of us probably did just that in 2007, albeit begrudgingly, after Black Cat Games’ blog completely ceased to receive news updates on their forthcoming commercial game, Alien Swarm: Infested.
Though their previous project, the original Unreal Tournament 2004 mod version of the game (that you can still try out and play, by the way; its unrelenting difficulty level and gritty gameplay is something to behold), illustrated in the screenshots below, had laid down a steel-solid foundation for future games to build on, their PR unfortunately started mirroring Black Widow Games’ They Hunger: Lost Souls on the other side of the fence.
This is why I am all the more happy to report that more than three years later and completely out of the blue, Valve have just released Alien Swarm, a Source-based top-down co-op corridor shooter, completely free of charge.