Leaked files assemble a nearly complete, fully playable version of Portal prequel F-Stop
The missing pieces emerged
Leakers have assembled a playable version of F-Stop, a canceled Portal prequel that had remained lost for nearly 20 years. Most of its assets came from a 12-terabyte leak released in August.
That leak did not contain the source code or map data. Those components apparently appeared on the Valve Cut Content Discord this week, making it possible to put together a nearly complete build.
A camera drives the puzzles
F-Stop differs sharply from the mainline Portal games. Players use a camera to capture an item in a picture, then place it elsewhere using the resulting Polaroid-like image.
Some dialogue and elements from F-Stop eventually appeared in Portal 2. The camera-based mechanic has also been compared with the one in Viewfinder.
A short experimental project
Videos showing the entire F-Stop campaign each run for under an hour. The game was developed during Valve’s “Directed Design Experiments,” a three-month period in 2007. During that period, Valve split into five teams to create video game experiments.
Key points
- A playable version of canceled Portal prequel F-Stop has been pieced together.
- Most assets came from a 12-terabyte leak in August; source code and map data appeared later.
- F-Stop uses a camera to capture items and reposition them through pictures.
- Videos of the full campaign run for less than an hour.