Half-Life 2 is 20 years old and has been updated with Steam Workshop support and developer commentary

rockpapershotgun.com:

Half-Life 2 just turned 20 years old, and to celebrate Valve have released an update for their classic first-person shooter. In brief: they've recorded developer commentary; they've added Steam Workshop support; Episodes One and Two are now part of the package; and there are some bug fixes and new graphics options.

Grab it before the end of the weekend (November 18th at 6pm GMT) and it's also free to keep on Steam.

Episodes 1 and 2 already had developer commentary, as do several other Valve games, but Half-Life 2 never did. This update adds three and a half hours of commentary by members of the Half-Life 2 team, as they try to remember what the heck happened during the making of the game.

If you're not familiar with the story of Half-Life 2's development, the answer is: a lot happened. Valve also partnered with Secret Tape to produce a two-hour documentary on the subject:

Half-Life 2 had a bustling modding community back when, just as its predecessor did, and it's great that Steam Workshop support has been added even if it's late. (Steam Workshop itself was only created in 2011.) It's already filling up with work now.

The full list of fixes and rendering options is too long for me to include here. There are changes to support ultrawide monitors and high FOV settings, increased spawn points in multiplayer maps to thwart players who are a quickdraw with a toilet, and some limits lifted within BSP files allowing for modders to place more brushes and models within their own levels.

Valve did a similar set of revisions to celebrate the original Half-Life's 25th anniversary last year. Next year will be the 20th anniversary of Day Of Defeat: Source, so I'm looking forward to the three hour-long documentary about that.