GoldSrc (Half-Life Engine) - 1998

GoldSrc is a game engine developed by Valve Software, first used in the 1998 first-person shooter game Half-Life.
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GoldSrc (Half-Life Engine)
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Half-Life - 1998
Hostile Intent - 1998
Sven Co-op - 1999
Team Fortress Classic - 1999
Action Half-Life - 2000
Battle Grounds - 2000
Bumpercars - 2000
Counter-Strike 1.6 - 2000
Earth's Special Forces - 2000
Frontline Force - 2001
and 7 more...
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Source (Half-Life 2 Engine) (2004)