1998 - Half-Life

1999 - Half-Life: Opposing Force

2001 - Half-Life: Blue Shift

2001 - Half-Life: Decay

2004 - Half-Life: Source

2004 - Half-Life 2

2004 - Half-Life 2: Deathmatch

2005 - Half-Life 2: Lost Coast

2006 - Half-Life Deathmatch: Source

2006 - Half-Life 2: Episode One

2007 - Half-Life 2: Episode Two

2020 - Half-Life: Alyx