Fast multiplayer action set in the Half-Life 2 universe! HL2's physics adds a new dimension to deathmatch play. Play straight deathmatch or try....

Just updated to include player stats, achievements, new scoreboards and more!

Supports cross-platform Steam Cloud - continue your game on any supported OS. Plus, all new Steam achievements!

The "Perpetual Testing Initiative" has been expanded to allow you to design co-op puzzles for you and your friends!

Set in the zombie apocalypse, Left 4 Dead 2 (L4D2) is the highly anticipated sequel to the award-winning Left 4 Dead, the #1 co-op game of 2008....

From Valve (the creators of Counter-Strike, Half-Life and more) comes Left 4 Dead, a co-op action horror game for the PC and Xbox 360 that casts up to f

Counter-Strike: Global Offensive (CS: GO) will expand upon the team-based action gameplay that it pioneered when it was launched 14 years ago. CS: GO...

Nine distinct classes provide a broad range of tactical abilities and personalities. Constantly updated with new game modes, maps, equipment and...

Garry's Mod is a physics sandbox. There aren't any predefined aims or goals. We give you the tools and leave you to play.