Massive Steam leak exposes Valve prototypes and canceled Half-Life 2: Episode 3 assets

The archive is so large that researchers are still cataloging it, but users have already found assets linked to the canceled Half-Life 2: Episode 3, cut content from Portal 2, and a build of F-Stop, a Portal-universe game built around a camera mechanic that can manipulate real-world objects. The trove also includes beta and final versions of Valve franchises such as Half-Life, Left 4 Dead, Portal, and Counter-Strike: Global Offensive, as well as titles from third-party developers. Early versions of Call of Duty, Resident Evil, Mirror’s Edge, Batman: Arkham Asylum, and Dragon Age: Origins have been identified, along with games from major franchises like Fallout and Civilization and works by indie developers. A catalog on GitHub lists most of the included titles.

Sleuths have reportedly pulled deleted Portal 2 dialogue that changes the context of Companion Cubes, alternative intro and GLaDOS sequences, and a version of the Weaponizer intended for Half-Life 2: Episode 3. Social media posts have circulated with screenshots and clips from the leaked files. One X user, Gabe Follower, said the leak was made possible through a publicly accessible endpoint, which may explain why the files appear to stop around 2013, when Valve reportedly switched storage systems.

Valve has not commented on the leak. Engadget said it reached out to Valve and would update its story when it heard back. Because Valve has not confirmed the contents, the reports note that the material should be treated cautiously.