This offer on Steam lets you sample all titles in the franchise before the release of Alyx in a few months.
It's a mode from ex-Valve employee Cayle George.
It's no Half-Life 3, but it's a good sign of things to come for the series.
The nearly twenty-year-old game has been patched.
Valve have spoken out about the Half-Life 3 speculation.
Or should we say lack of.
Artist David Thany was commissioned to design them the Steam Summer Sale in 2013.