Valve has released the Half-Life 2 Anniversary update to celebrate the game’s 20th anniversary, adding developer commentary, improved the graphics and lighting in the game, Steam Workshop support, and bundled in Episode One, Episode Two, and Lost Coast all into Half Life 2. You can also grab Half-Life 2 and all of this content for free from Steam. There is also a new 20th anniversary documentary that explores the game’s history and development.
The full patch notes for Half-Life 2 Anniversary Edition are as follows:
Additionally, Valve has also announced that it will be reprinting Raising The Bar, an expanded edition of the original book that was first printed in 2004. This second edition of Raising The Bar adds new concept art from Episode One and Episode Two, plus a look at the never released third episode. It will be released in 2025.
Source: Half Life website
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