In the Gun Game mod for Counter-Strike: Source, players begin with a handgun and progressively gain more powerful weapons by racking up kills. Valve didn't reveal how Gun Game would be tweaked for Arsenal, but it did note it is working directly with Gun Game's creators, and the two modes will add eight new maps.

"We are excited that Valve reached out and is working with us to ensure Arsenal Mode is the best version of Gun Game," Gun Game project lead Michael Barr said in a statement.
Counter-Strike: Global Offensive is in development for Windows PCs, Mac OS, Xbox 360, and PlayStation 3. The game is scheduled for release in "early" 2012.

