The developers have managed to get this complex mod to the Linux platform
No More Room in Hell, one of the best Half-Life 2 mods ever made, has arrived on Steam for Linux.No More Room in Hell is a completely free cooperative FPS that features Dynamic Objective Maps that change with every playthrough, a realistic approach, a survival mode, and multiple opponents.
A few months ago, the developers were looking for Linux Beta testers and I guess they found them because the game has been launched on Steam for Linux and it seems to be working without a hitch.
What's even more interesting is the fact that this is a completely free game. Even so, it had to pass through the Steam Greenlight program, but it wasn't really an obstacle.
The Linux system requirement are also pretty close to Half-Life 2: Ubuntu 12.04, a Dual core processor from Intel or AMD at 2.8 GHz, 2 GB of RAM, nVidia GeForce 8 series or better, ATI/AMD Radeaon HD2600/3600 (Graphic Drivers: nVidia 310, AMD 12.11) and OpenGL 2.1 support, 5 GB of hard-disk space, and an OpenAL Compatible Sound Card.
More details about this game can be found on the Steam website.