Valve’s cancelled Portal prequel, F-Stop, leaked online as a fully playable build. Kotaku reported that the build combines three separate Valve leaks.
What the Portal prequel F-Stop was
In 2007, Valve spent three months on a project Gabe Newell later called the Directed Design Experiments. Valve split into five teams. Each team designed and partly built a game “experiment”. The fifth was F-Stop.
F-Stop was a prequel to Portal. Players used an experimental Aperture Science camera to change perspectives and solve puzzles.
Newell was taken with it, but playtesters were less keen. Valve scrapped the game. Some of its dialogue, characters and mechanics were reworked into Portal 2, according to Kotaku.
How three leaks became one playable game
The first piece came from the Steam2 leak in late August. That leak was roughly 13TB of Steam depot data from 2003 to 2013, and it included most F-Stop assets. We covered it in our report on the Steam teraleak.
It didn’t include the source code or the mapsrc data, which is Valve’s folder for map source files. Kotaku says both appeared on the Valve Cut Content project’s Discord server over the past 48 hours.
According to the server’s mods, the person who leaked the mapsrc first asked for $1,000. They ended up releasing it for free. The Valve Cut Content team says it has verified the map files, and the community then combined all three leaks.
What the leaked build shows
Players say the build is essentially 99% complete. A few assets and dialogue lines are missing.
Kotaku’s writer called it a big step up from the “0% complete” build fans saw a week earlier. He said Valve would probably have added more polish had it ever planned an official release.
Kotaku credits several leakers and the Valve Cut Content team for the work. The lead image is a still from a ToothpasteVixen video of the build.
Kotaku’s report doesn’t include a comment from Valve, and we haven’t seen one. There is no word on any official release. The build is described as playable in “almost” its entirety, so expect some gaps.
FAQ
What was F-Stop?
F-Stop was a cancelled 2007 Portal prequel from Valve. Its puzzles used an experimental Aperture Science camera to manipulate perspective.
Is the leaked F-Stop playable?
Yes. Players report the build is about 99% complete, with a few missing assets and dialogue lines.
Did Valve release F-Stop officially?
No. Valve cancelled it and reused some of its ideas in Portal 2. Kotaku’s report includes no comment from Valve.
