Tripwire Interactive and Teotl Studios have written separate postmortems for their respective participation in the Valve ARG for Portal 2. Both describe the thoughts and ideas that went into the ARG, how each studio created their own custom content for the game, and lessons learned.
From Killing Floor's Postmortem:
The final “clue” in wave 1 was one of our own creation, that while found, was never understood. Harchier Spebbington, the main character from The Ball had his profile changed to “Ask Hey Vie”. This is an anagram for I Have Keys. And while it was noticed, nobody hunted down Mr. Spebbington to ask him for a key. He could be found on the Tripwire forums for Killing Floor and The Ball. To all the Red Orchestra fans out there, one of his many keys was a Red Orchestra 2 beta invite! But his key giving days are over for now, so please don’t come asking!(...)
Coming away from it all we felt we did many things right, having never participated in an ARG before or having worked with so many other studios at the same time coordinating this massive effort. But at the same time there were hard lessons that were definitely learned both in ARG design and getting the message to your existing player base that they need to pull back the curtain and look beneath. Many of our puzzles were designed with the KF hard core community in mind, and they were near the last of the major groups to pick up that something was going on besides an elaborate April Fools joke (“the secret is to bang the rocks together, guys”). One thing that really worked in our favor was our watching over the ARG players and being able to react dynamically to them being stuck and deciding on new puzzles and hints to guide them forward. All of our in-game news updates as well as our Achievement Glyph puzzle were designed within hours of them going live as a reaction to the state of the ARG players!
From The Ball's Postmortem:
Just like all other games involved we hid a letter, a sentence, and a glyph into the game. Into the Oztoc I large secret area, in the large low gravity room to be specific.
This got discovered fairly late unfortunately. Given that we had all three at the exact same place, if people would have discovered ours sooner they would have immediately realized that they were looking for one of those in each game. Instead, they spent the majority of time hacking our files and going way to deep into everything. A problem that hit most of the games. People spent more time looking at the files than actually simply playing the games. We deliberately placed the glyph and such fairly deep into the game to make sure that people wouldn’t just discover it on their first play session. We wanted people to actually play and experience our game.
The final “clue” in wave 1 was one of our own creation, that while found, was never understood. Harchier Spebbington, the main character from The Ball had his profile changed to “Ask Hey Vie”. This is an anagram for I Have Keys. And while it was noticed, nobody hunted down Mr. Spebbington to ask him for a key. He could be found on the Tripwire forums for Killing Floor and The Ball. To all the Red Orchestra fans out there, one of his many keys was a Red Orchestra 2 beta invite! But his key giving days are over for now, so please don’t come asking!(...)
Coming away from it all we felt we did many things right, having never participated in an ARG before or having worked with so many other studios at the same time coordinating this massive effort. But at the same time there were hard lessons that were definitely learned both in ARG design and getting the message to your existing player base that they need to pull back the curtain and look beneath. Many of our puzzles were designed with the KF hard core community in mind, and they were near the last of the major groups to pick up that something was going on besides an elaborate April Fools joke (“the secret is to bang the rocks together, guys”). One thing that really worked in our favor was our watching over the ARG players and being able to react dynamically to them being stuck and deciding on new puzzles and hints to guide them forward. All of our in-game news updates as well as our Achievement Glyph puzzle were designed within hours of them going live as a reaction to the state of the ARG players!
From The Ball's Postmortem:
Just like all other games involved we hid a letter, a sentence, and a glyph into the game. Into the Oztoc I large secret area, in the large low gravity room to be specific.
This got discovered fairly late unfortunately. Given that we had all three at the exact same place, if people would have discovered ours sooner they would have immediately realized that they were looking for one of those in each game. Instead, they spent the majority of time hacking our files and going way to deep into everything. A problem that hit most of the games. People spent more time looking at the files than actually simply playing the games. We deliberately placed the glyph and such fairly deep into the game to make sure that people wouldn’t just discover it on their first play session. We wanted people to actually play and experience our game.