DoD: Source takes the classic teamplay of DoD and expands the experience with Source, the engine technology Valve created for Half-LifeĀ® 2 and it's next generation of games. With this technology, DoD: Source offers state of the art graphics with optimized versions of popular maps and all new player, weapon and world models, plus support for HDR lighting. DoD: Source leverages the power of the Source engine by introducing advanced sound technology to provide a more immersive soundscape and integrated physics simulation technology for ragdolls and physically simulated objects throughout each map. DoD: Source will be available for pre-load and pre-order next week. Those who purchased the Half-Life 2 Silver or Gold Steam offers will receive a request to pre-load the game at this time and will receive access to play the moment the game is made available.