Valve Releases Updated Alien Swarm For Free With Code Base
baronvoncarson tips news that today Valve released an updated version of Alien Swarm, a popular Unreal Tournament 2004 total conversion mod. The creators of the mod were hired by Valve, and they've helped turn it into a stand-alone game running on the Source engine. Valve is also releasing the code base for Alien Swarm and an SDK. The game is available for free on Steam.
From the summary: "The creators of the mod were hired by Valve, and they've helped turn it into a stand-alone game running on the Source engine."
They hired the team that made it for the Unreal engine, and had them re-create it with the Source (Half-Life 2 etc) engine.