MIT Mystery Hunt Wrap-Up Part 2

Part 1. Part 2. Part 3. Part 4. Part 5. Part 6.

(SPOILER ALERT: THESE POSTS CONTAIN DETAILS OF PUZZLES FROM THE HUNT INCLUDING HOOKS AND ANSWERS).

As soon as introductions were finished, we started working on the three puzzles that were already open. One was a pop-culture puzzle, one was a hands-on puzzle and the third was a very hard Sudoku puzzle. That’s what I worked on with about 5 others. As you can see, nothing is filled in in the grid. Instead, you have a logic puzzle to solve which numbers are given to you in the grid. Sudoku grids typically have a rotational symmetry associated with them, so we were able to use clue-by-clue to eventually obtain a solvable Sudoku grid. You then plug the numbers you get into the equations given and it spells out INTRUSION.

As soon as puzzles are solved, more puzzles open up. I worked on a fairly easy word puzzle called Opposites are not Downbeats where the first half of the clue has an answers with a negative prefix that is not used as a negative, followed by what you get when you remove that false prefix. For instance, “To mistreat is not to employ” yields ABUSE and USE. Reading the first letters of the second words gives the answer.

I also looked at How Puzzling These Changes Are which contained a bunch of lines with 12 words each. It turned out these were the nth word in a chapter of Alice in Wonderland that had some property. For instance, the first set of words is the first seven-letter word in the chapter, except for chapter 1. The second set was the forty-second word (note the Hitchhiker reference) from the end of the chapter, and so on. Using my relatively obscure programming language of choice (GAP), I imported the text of Alice in Wonderland, broke it up and got to work. I’d note that it did take us a while to figure out that this was exactly what was going on. Now, for each of these twelve sets, one of the words was wrong, so we had to find the correct word with that property. At this point, we stared for a while and finally my friend Mike sat down next to us and immediately noticed that all of our extra words had a ‘t’ as the middle letter! We then found that this was the first odd-lettered word in the chapter with that property, except for one word. Finding the correct word for that chapter gave us the answer.

There were other cool puzzles in this round, including a Scooby Doo puzzle one with Singing Bees and one with a Swype keyboard. For the last two of these, when someone had the necessary “aha”, the entire room went “ohhhh”. (It was awesome).

There were three metapuzzles associated with this round, one for spades, one for clubs and one for diamonds. The spades meta was very cool. It had eight puzzles and the first answers we had were INTRUSION, ARRAY and MEMORY, so we at first thought something computer-related. But it was soon discovered that these were all collective nouns for animals (an Intrusion of Cockroaches, an Array of Hedgehogs and a Memory of Elephants). Absolutely none of these were standard ones, especially since they tried to get something unique to one animal. Each puzzle had a playing card associated with it, and reading the first letters of the animals in card order, you got the meta answer. Late Sunday morning when we had some time to kill, we submitted answers to the few puzzles in this round we didn’t solve. For instance, we knew the meta-answer letter was O, so we guessed answers like Parliament (of owls), but it turned out to be a Wobbling of Ostriches. (Later that night, I was shown this link which describes collective nouns for mathematicians). Once we solved all three metas here, we were sent on a runaround finding posters around campus with QR codes and a playing card on them.

Then came the much harder rounds.

Part 1. Part 2. Part 3. Part 4. Part 5. Part 6.