Series:Half-Life

Half-Life
Half-Life	1998
Sven Co-op (unofficial mod)	1999
Half-Life: Opposing Force	1999
Half-Life: Blue Shift	2001
Codename: Gordon	2004
Half-Life: Source	2004
Half-Life 2	2004
Half-Life 2: Deathmatch	2004
Half-Life 2: Lost Coast	2005
Half-Life Deathmatch: Source	2006
Half-Life 2: Episode One	2006
Half-Life 2: Episode Two	2007
Portal (series)
Half-Life: Decay (unofficial port)	2008
Transmissions: Element 120 (unofficial mod)	2016
Hunt Down The Freeman (unofficial game)	2018
Half-Life 2: Year Long Alarm (unofficial mod)	2018
Black Mesa (unofficial remake)	2020
Half-Life: Alyx	2020
Half-Life: Absolute Zero (unofficial mod)	2020

Game		Developer	Publisher	Released	OS
	Codename: Gordon	Nuclearvision Entertainment	Valve Corporation	May 17, 2004
	Half-Life 2	Valve Corporation	Sierra Entertainment, Valve Corporation, 1C-SoftClub, Buka Entertainment	November 16, 2004
	Half-Life 2: Deathmatch	Valve Corporation		November 30, 2004
	Half-Life 2: Episode One	Valve Corporation	Valve Corporation, Buka Entertainment	June 1, 2006
	Half-Life 2: Episode Two	Valve Corporation	Valve Corporation, Buka Entertainment	October 10, 2007
	Half-Life 2: Lost Coast	Valve Corporation		October 27, 2005
	Half-Life: Alyx	Valve Corporation		March 23, 2020
	Half-Life: Blue Shift	Gearbox Software	Sierra Entertainment, Valve Corporation, Buka Entertainment	June 12, 2001
	Half-Life	Valve Corporation	Sierra On-Line, Valve Corporation, Buka Entertainment, Brasoft	November 19, 1998
	Half-Life Deathmatch: Source	Valve Corporation		May 1, 2006
	Half-Life: Opposing Force	Gearbox Software	Sierra On-Line, Valve Corporation, Buka Entertainment	November 19, 1999
	Half-Life: Source	Valve Corporation		November 16, 2004