Named Game of the Year by over 50 publications, Valve's début title blends action and adventure with award-winning technology to create a frighteningly realistic world where players must think to survive. Also includes an exciting multiplayer mode that allows you to play against friends and enemies around the world.
Scientist SlauterHouse: Mod Messup #1 - WTF ..(or shortened to SSH:MM1:WTF) is a crazy spin-off of the classic Scientist Slauterhouse that brings you back into Black Mesa, but as a different character with a different role.
This mod is already on the site, you should probably take my advice and remove it.