For five months in 2008, Valve Software was making a version of Portal 2 that wasn't going to include Portals. And it was going to be a prequel, set in the '50s. The game, based on an internal prototype called F-Stop, was built around a new gameplay mechanic that thrilled people at Valve.


But the feedback from test players was harsh, according to journalist Geoff Keighley, who reveals the story in "The Final Hours Of Portal 2," a slick multimedia app that launched today on iTunes.

Back in '08, those uneasy test player wanted portals in their Portal 2. They wanted Chell and GLaDOS, the minimal cast of the first Portal to be in Portal 2.




F-Stop's amazing new gameplay mechanic remains a mystery to those outside Valve. Keighley says that Valve asked him to keep a description of it out of his behind-the-scenes chronicle, but he has stuffed about 15,000 other words about the making of Portal 2 — plus exclusive images and video — in an app that reads and functions like a futuristic magazine article.

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In the $2 app, Keighley makes the most of an unprecedented amount of access he got to Valve during the last several years. Taking time out from hosting his Game Trailers TV show on Spike, he spent some of his time as a wallflower at Valve, watching the ups and surprising number of downs in the development cycle of a game that, this week, is earning critical raves.

The app includes concept art from F-Stop (including the image above), videos of a scuttled Valve game called Two Bots, One Wrench, and even an interactive widget that lets a user learn how the game's portals work. The main draw of the app, however, is Keighley's lengthy making of story that includes mini-profiles of the eclectic team behind the game, from the male Portal 2 developer who gets one haircut a year to the lady who used to puppeteer the Red Fraggle in Jim Henson's Fraggle Rock.


There are minor Portal 2 spoilers in Keighley's story, but anyone who is curious about the game and is armed with an iPad definitely should grab this. It's a good place to find out which Half-Life reference was cut from Portal 2, what crazy games Valve was making during a three-month period when the studio took a break from all of its scheduled projects, and you'll even find out how we here at Kotaku made Valve very nervous a few years back. (Okay, can't resist telling some of that one here.... In June, 2008, we uncovered a casting call for the role of Cave Johnson and reported the guy would be part of Portal 2, back when Valve was still making the F-Stop version and Cave was scripted to lead a robot revolution and put the player on trial. Valve considered cutting Cave).


Keighley's app is live now on iTunes. Get it.

The Final Hours of Portal 2 [iTunes]