Alien Swarm

Developed by a team of Valve designers recruited from the modding community, this release provides the game and Source SDK free of charge. It immerses players in a massive bug hunt combining cooperative gameplay with tactical squad mechanics. Team up with friends to control a squad of four different IAF Marine classes, strategizing with an unlockable arsenal of weapons and numerous loadout configurations to fight diverse aliens. Navigate through an overrun off-world colony, exterminating the infestation across environments ranging from a frozen planetary surface to a lava-filled underground mining facility. The package includes the complete code base for Alien Swarm, featuring Source engine updates and the SDK, adding a third-person camera, depth of field, enhanced dynamic shadows, and various gameplay tweaks. The title includes tactical 4-player co-op action with a top-down view, complete game code and mod tools, unlockable persistent items by leveling up, over 40 weapons and equipment options, four unique classes and eight characters, matchmaking, Steam Cloud, Steam Stats, 64 achievements, a tile-based map generation tool, and is powered by Source and Steam.