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Counter-Strike (commonly abbreviated to CS) is a tactical first-person shooter video game which originated from a Half-Life modification by Minh "Gooseman" Le and Jess "Cliffe" Cliffe. The game has been expanded into a series since its original release, which currently includes Counter-Strike: Condition Zero, Counter-Strike: Source, Counter-Strike: Anthology and Counter-Strike
Counter-Strike: Condition Zero (abbreviated CS: CZ or just CZ) features a multi-player mode, which mostly features updated character models, textures, maps and other graphical tweaks. Unlike other Counter-Strike games, Condition Zero also contains a single player mission pack with the player unlocking maps and more efficient bots as they pass certain requirements for each map while playing as a counter terrorist. These requirements include targets such as, "Kill 3 enemies with a glock" or "Win a round in 45 seconds." Condition Zero also contains bots with better AI than other Counter-Strike games.
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