Counter Strike 1.6

Counter Strike v1.6 is the world’s number one online action game series, is a first-person shooter which is developed by Valve Software, the creators of the renowned Half-Life series. This team-oriented online shooter pits terrorists and counter-terrorists against one another in round-based combat set all over the world. Using the power of the “Source” engine, the original Counter-Strike has been completely remade as Counter-Strike: Source—offering upgraded graphics, levels, and the implementation of a new physics engine. Counter-Strike will never be the same!
Counter-Strike began as a simple fan-produced mod for Half-Life. Thanks to a series of steadily-improving beta releases. As the fast-paced, tactical game play was refined and improved, and as new concepts and maps were introduced, Counter-Strike moved from being a mere Half-Life mod to an entirely new game.