Be warned though, this article contains spoilers!

The ARG consisted of three phases that each updated all the participating games with more clues and puzzles. Each phase would reveal a little more of the connection with Portal 2, until—finally—GLaDOS would reveal herself in the games. I’ll take you on the tour and show you what we did for both Toki Tori and RUSH per update. Enjoy!

Update 1

The first update was meant to look like an April fools joke with a potato theme, but its ARG goal was to disclose a number of gibberish sentences, some glyphs and the letters that were linked to those glyphs. The glyphs are all connected with games participating in the ARG and had to be used in a later update to retrieve a crucial password.

We changed the bouncing Toki Tori in the main menu to “Potatoki”. All other menu appearances of Toki were potatofied as well.

While Potatoki is kind of funny, the real content can be found when your profile name contains “potato” in some way. The proud owners of a starch based profile name would suddenly see a new button in the world selection screen named “TEST”. Since the main profile name defaults to your Steam name we had figured that someone was bound to run into the hidden menu by accident. But, as it turned out, creating a profile named “potatofoolsday” (which happens to contain potato) was tried first and accepted as the way to unlock the new world.

The TEST world contained three brand-new levels and a new item: the shower curtain. The shower curtain was of course a reference to Aperture Science’s origins. The level texts all contained “//TODO” markers and placeholder text to try and make it look like it was not meant to be released yet.

The text for the third level however was a little more substantial and mentioned a boy who lived 187 years ago and contained some deliberate typos. 187 years ago, the 15 year old Louis Braille invented his famous Braille system. The walls in the levels featured light-patterns which represented the longitude and latitude of the location where we hid a poster with a gibberish sentence and the link between a glyph and a letter.

In one of the sentences “late” was misspelled as “lat” which is short for latitude. That same sentence also had the word “long” in it which is short for longitude. Also the longitude was rotated to be vertically on the level, while the latitude was displayed horizontally. Pretty obvious, right?

When we found out that an IRC user that goes by the handle Jake_R was planning on visiting us, we rushed to our poster, put up some extra potatoes as hints and hid in the barber shop across the street to watch the show.

We also put up a subtle Portal reference on the exit signs, but that has never been found during the ARG.

The first RUSH update was slightly more humble: we simply put a “Potasteroid” in the main menu. If you’d click on the starchy comet a message pops up that read the gibberish sentence. Upon closer inspection, the Potasteroid contained a glyph and the letters C and K.

Update 2

Update two revolved around login screens and passwords. Each game had a secret way to open up an Aperture Science login screen and embedded a password for the login screen of another game. For example Toki Tori hid the password for Cogs’ login screen while Super Meat Boy would reveal the password for Toki Tori’s login screen.

Three new bonus levels appeared in the TEST world of which one had a sort of energy beam. If Toki stands in the beam, an Aperture Science login screen pops up and prompts the player for a password. We thought it was kind of neat that we now had two puzzles in one level: one to collect all the eggs and one to reach the beam.

Getting the password out of Toki was a bit more work. Each level in the second update displays one or more patterns of light and dark tiles. Each pattern can be merged with another pattern to eventually form a QR code. To merge the patterns correctly one has to match up the light patterns that appear on the tiles (awesomely hinted at by Hidden Path in their edit of the video we shot from the barber shop).

The QR code represents a link to a .zip file on the Toki Tori website. The file contained three fisheye photos: one of a monitor running the IRC chat, one of my desk and one where Meinte, Eelke, Collin and I were “afraid” (Meinte could not stop laughing so we made him put his hands in front of his face) of the camera. The camera itself was supposed to be GLaDOS inspecting our offices and threatening us.

But there is more to the photos than meets the eye. We modified the EXIF data embedded in the pictures and changed the aperture’s F number to 1473, which is 0x5C1 in hex, which can be read as “Sci” so that makes “Aperture Sci”.

We also replaced the embedded thumbnail with a completely different image. The new thumbnail contains some lines of pseudo code and a collection of boxes made out of curly and square brackets. The pseudo code was mostly meant for amusement—it would for example sort the mess on my desk—but when the thumbnail is overlaid onto the original image it reveals that each bracket box marks one letter. The clockwise sequence of the bracket boxes formed a number (a binary sequence actually where the square bracket is used as 0 and the curly bracket as 1) and if you put the letters in the order of the numbers it reveals the password for Cog’s login screen. Easy.

Fun fact: during the ARG nobody considered the fact that update notes could actually refer to something that has been updated. We actually fixed a small issue in the RUSH skybox because there was a slight color mismatch. The ARG community picked this up as a hint to look up, which was fine—although a complete coincidence—because we had put a secret code on the bottom of each level.

The first character of the code refers to one of the menus by its first letter, the second and third characters refer to a grid position in that menu. The number that follows after the dash refers to a letter in the level name found at the grid position in the menu from the beginning of the code. For example: T32-16 refers to the 16th letter of the name of the level that can be found in the Tutorial menu at column 3, row 2. The tutorial level at column three, row two is called “movement tutorial” so the letter would be an A (spaces count).

To get the password you have to follow the codes from one level to the next, collecting the letters they refer to on the way, until you would reach a level that has EOT as code. You can’t just start working on the password from any level. While any level produces something only one level results in the actual password. Which one? We figured that “the key to success” would make perfect sense since key and password are more or less synonymous. But to be sure, we also boxed that code to draw some attention to it.

Getting the Aperture Science popup in RUSH was not that hard on its own. We made a simple sketch of a familiar looking level with some signs marked on it. To open the popup you just have to place the signs as shown on the sketch. It took a while before the ARG community found out about it because the sketch was hidden in a rather hard puzzle in Amnesia.

Update 3

GLaDOS made her appearance in the third update. The hidden rewards this time are Aperture Science popups with GLaDOS audio clues.

The third update delivered three more Toki Tori bonus levels. Two of these were simply levels with no hidden content or puzzles in them, but the third one was different. For one, its level texts seem garbled and change over time. But most of all: it’s unsolvable. When the level is started Toki Tori is immediately stuck and has no items to do anything at all.

The garbled messages are not just garbled messages, we’ve made them to act like an automated emergency broadcast. The broadcast is telling the story of Eelke and me escaping the scene of the previous update’s photo and that we managed to secure the “payload” (i.e. a .zip file with the actual playable level) and store it online. We used the NATO phonetic alphabet to spell out the filename to download.

We also hid another photo with custom EXIF data and a modified thumbnail in the game files. This photo showed Meinte and Collin on the floor and pseudo code that suggested that GLaDOS removed the bonus level and offloaded it to a secure location. The pseudo code also shows where to place the downloaded level.

Once you replace the impossible level with the downloaded level, GLaDOS will appear in the background and she will mock Toki Tori whenever he collects an egg. The energy beam from the second update reappears in this level and it too opens a popup when Toki Tori stands in it.

In RUSH we added a chance that GLaDOS will challenge you whenever you start a level. The chance is based on the difficulty level: tutorial levels never trigger GLaDOS, easy level have a very small chance, medium a somewhat better chance, hard and bonus have a fair chance and the hidden levels trigger GLaDOS about one third of the times.

When the challenge is triggered, she will ridicule the complexity of the puzzle and then raises the stakes by disabling the hints. If the level is successfully solved with the hints disabled she congratulates you and unlocks the “Actual Challenges”.

The Actual Challenges contain 5 new levels that unlock sequentially. The hints are disabled for all of these levels and we tried our best to make them stand out from the rest of the levels. And, also, to make them hard. It was amazing to see that the ARG community burned through them in just a couple of hours or so. Well done!

Every Actual Challenge level starts with a snappy GLaDOS line and when the level is completed she’ll congratulate the player in her own way. And the cubes, they look a little different in these levels:

The last level of the actual challenges looks and, as a matter of fact, is pretty different than the other four levels. The level looks complex but if you would just press play, it would complete successfully without even placing a single sign. However, if you do that GLaDOS will tell you that you obviously did not understand what you were supposed to do. If you instead send the cube on a massive detour it will leave a trail of glowing letters and glyphs. Those letters and glyphs form the password for the popup that opens when you finish the level (RUSH’s popup was the only popup in the third update that was protected with a password).

The future

As you might have noticed, we’ve put a lot of effort and content in our ARG updates, but what will happen with them now that the ARG is over? Well, we obviously keep all the new levels but we’d like to preserve some of the ARG mystery in there as well. Mostly for those who missed out or weren’t there when the ARG happened to figure some of it out.

Some small things will change or revert back to the old—pre-ARG—situation though. The Potatoki will change back to regular Toki Tori, the Potasteroid will become a regular asteroid and we’ll probably change the way the last Toki Tori bonus level must be unlocked.

So that was our side of the ARG. Feel free to drop any questions (and post-ARG suggestions) you have about our part in the comments below.

Finally, be sure to check out the awesome ARG wiki that the community has built during the ARG. It contains a lot of information on the overall structure of the ARG and the other games!