When Portal 2 was announced, the news dropped through an elaborate scavenger hunt puzzle that sent thousands of players crawling all over the internet. Years later, we finally get to see some of the work that went into making that alternate reality game, as told by celebrated Half-Life modder (now Valve employee) Adam Foster in a blog post at Gamasutra.

Foster, one of the designers of the ARG puzzle from Valve, describes the elaborate trail of puzzles that the Portal-playing community was able to decipher. It began with a seemingly mundane game update for Portal 1: “changed radio transmission frequency to comply with federal and state spectrum management regulations.” That update changed the radios found throughout Portal into Morse Code-dispensers. The code was deciphered into slow-scan television images. Somehow—my knowledge of information theory and cryptography ran dry a paragraph ago—these images were combined into an elaborate code, which was then hacked. Remember: none of us is as smart as all of us.



The result? A phone number to an ancient modem in Foster’s kitchen that slowly drip-fed Portal 2 concept art to announce the game to the world. The ARG team at Valve did a fun thing with no budget, and it caught the attention of the world’s games media. It was also an intricately designed puzzle that, despite a few false positives, played out exactly as Valve designed. As Foster writes, “Estimated time to 'solve' the initial puzzles: seven hours. Actual time to solve: seven hours and sixteen minutes. This wasn't an accident.”

We are all just puppets dancing on Gabe Newell’s strings, aren't we? Check out the full blog post from Foster for a lot of fascinating details about ARGs and the devious geniuses at Valve.