The highlight is of course Half-Life 3, one of five cancelled Half-Life games worked on in the 13 years between the release of Half-Life: Episode 2 and this year's Half-Life: Alyx. IGN has a tidy roundup of the various cancelled projects. Geoff Keighley's The Final Hours of Half-Life: Alyx released this week on Steam, and it reveals Valve's failed attempt to make Half-Life 3 - the game boss Gabe Newell would refuse to discuss in interviews. Over the last decade Valve cancelled quite a few video games, and thanks to a recent documentary on the developer, we now have an idea of what exactly fell by the wayside.