Counter Strike 1.6.
Counter Strike 1.6 - It's a very popular first-person shooter around the world that was released on September 15, 2003. This game has quickly enslaved millions of players around the world, it's a team game and the main purpose of the game is to fight two teams (terrorists and policemen) with knives, shootguns and grenades, CS 1.6 game have few different map and gameplay types, this game have a lot of game servers and server-side modifications (Counter Strike 1.6 have singleplayer and multiplayer game modes) - CSDM, Zombie Plague, DeathRun etc.
Counter Strike 1.6 is all times most popular FPS genre game, you can download it absolutely for free and you can do it directly or using torrent application, download links is below this text. Read more about Counter Strike game.