Half-Life 2:

Enormous 12TB Steam leak includes abandoned Half-Life 2: Episode 3 assets

12TB Valve archive leak includes early Portal 2 builds and hints of Half-Life 2: Episode Three

Half-Life 2: Episode 3 doesn't exist because Left 4 Dead does

'My personal failure was being stumped': Gabe Newell says finishing Half-Life 2: Episode 3 just to conclude the story would've been 'copping out of [Valve's] obligation to gamers'

Gabe Newell says Half-Life 2: Episode 3 didn’t happen because he was ‘stumped’

Half-Life 2: 20th Anniversary Update