20. Valve Part 4: Half Times Two (2009)

From Half-Life to Left 4 Dead 2, Valve has been one of the trailblazers of the video game industry. In this fourth episode of our retrospective, watch and see how Valve's long-delayed Half-Life 2 is finally unleashed onto the world next to Steam, its digital distribution service.

Release date: 2009-11-16