anderson's Puzzle Blog

DASH 9 recap

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I participated in DASH 9 today in Fremont. First off, thanks to all of the organizers for a very smoothly-run event and for the great puzzles, as well as to Albert, Ben, Nathan, and Patrick for being great teammates.

Our team name was “)(()” (the joke is that it’s a palindrome, although no one believes it at first). We ended up getting 2nd place, which was certainly a pleasant surprise. Other teams with Galactic Trendsetters members got 3rd, 13th, 14th, and 16th, and our sister team “())(” got 55th, so it was a pretty good showing overall. Congratulations to everyone!

I’ll briefly discuss some puzzles now, so spoiler warning. Also, I’ll edit this post to include a link to the puzzles whenever they get posted.

The puzzles were very clean, and I especially enjoyed the reuse of the wooden pentagons over the various puzzles. In particular, the puzzle where it all came together and you had to build the 9-piece alien artifact (What Did We Miss?) was my highlight of the hunt; unfortunately, the free hints we got for solving part 1 did lessen the experience a bit by revealing a lot, but it was still a great puzzle nevertheless. It was super elegant how all of the translations you already performed had to be retranslated to new messages, and needing to build the artifact in 3D when all of the other puzzles were on a plane was a great aha (Ben: “It really added a whole new dimension to the puzzle!”)

I also enjoyed the word-search puzzle, Wide Field Array, which was quick but very clever, as well as the cryptic, Find the Landing Location, which had a neat twist. I have one minor complaint with Peacekeeping, in that it was probably faster to brute-force all of the possible positions of the 5 pentagons to find one that spells out a word, rather than the intended method of solving the logic puzzle with the transparencies. We did solve it as intended and it is a nice puzzle, but the shortcut is a little unfortunate. The only puzzle I had any real complaints about was the final one, Prevent Hostilities, because the AR was kind of finicky and the final step of pressing the porthole was unclued and not very interesting: why not just have the message display once you enter the correct 12 colors? We only got it because Ben decided to swipe on the screen and see what happened; if not for him, we likely wouldn’t have solved it until the second hint release.

Our puzzle timings were really unfortunate throughout the day. To calculate bonus, Cluekeeper rounds your time down to the nearest minute, so that solving a puzzle in 6 minutes and 1 second is worth one less point than 5 minutes and 59 seconds. Imagine our dismay when the seconds of our first 5 solve times were 8, 12, 1, 2, and 10 (I think I audibly cursed after the 1 second one, because we actually had the answer WEARECOMING but couldn’t parse it correctly for half a minute). When we then solved What Did We Miss? with a time of 16:01, I could only laugh at the absurdity of it all. At some point, we were sure that we would finish behind a team while having a lower total solve time, though that luckily ended up not happening. It was pretty close though, as evidenced by the fact that we lost by 2 points, but only by 11 seconds in terms of total solve time.

Our solve times

Another thing you might notice if you check the results page is that we took more than 6 hours to finish the hunt, more than many other teams. I can explain this: a few years ago, some of us participated in the Palantir Puzzle Hunt, which has the same format as DASH. We solved the puzzles themselves fairly quickly, but we ended up taking bathroom breaks between almost all puzzles because someone always had to go. In the end, I think we may not have been the first to finish, but we won by a comfortable margin because of all of the time we spent not doing puzzles, and so the “bathroom break strategy” was born.

We also employed the “bathroom break strategy” this DASH to an extent, though we were also slowed down by lunch taking forever and by getting lost on the walk to the last puzzle (oops).

Ben’s 1 lb burger (holy moly it’s so big)

Finally, Ben made 3 puns today which are too good not to share, so here we go:

  • During lunch, we were talking about the number 4 because of the answer WITNESS THIS PRIMAL FORCE. This caused Ben to make the observation “if you take a fork and remove one of the tines, would you call it a threek?” Ok fine this isn’t really a pun but it’s a truly profound observation.
  • Later, when we were hanging out at Albert’s house, we noticed that the Fremont site did pretty well, which led Ben to remark that for these teams, the hunt was “literally a walk in the park.” (note: the hunt mostly took place in the Fremont Central Park)
  • Finally, when Nathan was giving Ben and me a ride back, the streets near where I live are like October Drive, November Avenue, September Drive etc. Since this is the 3rd time Nathan has given me a ride, he commented that he could now navigate to my house without thinking, so I made some joke about how he would sleep-drive to my place. Then Ben interjects with “so you’re saying that you should wake him up when September ends” (!!!!!!!!!) Maybe I subconsciously set up the punchline, because I still can’t believe this happened.

Once again, thanks to all of the people who made DASH happen! It was a super fun experience and I enjoyed every minute of it.

Written by qzqxq

May 7, 2017 at 3:52 am

Galactic Puzzle Hunt 2017 recap: the puzzles

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The Galactic Puzzle Hunt took place about two six weeks ago, and overall, I had a great time helping create and run it and I’m really proud of everyone who contributed. There’s quite a lot of things I want to talk about, so this post will be dedicated to going over some of the specific puzzles; there will be another post for organization and other notes. There will be lots of spoilers, so be warned.

Before I get into the details, here are some personal puzzle recommendations if you haven’t seen them yet and want to try them out before being spoiled:

Now, for some specific puzzle commentary:

Read the rest of this entry »

Written by qzqxq

May 1, 2017 at 6:32 am

Puzzle 24: Trimino Divide

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This puzzle was made for WPC 2016 practice. Rules (from the IB): “Divide the grid along the given lines into triminoes. Each trimino is formed by three orthogonally adjacent cells. When there is a cross between two triminoes, they must be of a different shape. When there is a triangle between two triminoes, they must be of the same shape, but different orientation. When there is a dot between two triminoes, they must be of the same shape and the same orientation. Symbols always lie on a trimino border, not inside a trimino.”

Written by qzqxq

April 1, 2017 at 5:44 pm

Posted in Misc. Division, Puzzles!

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2017 Mystery Hunt recap

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The MIT Mystery Hunt happened two weekends two months ago, so here’s a (very belated) recap. It was my 9th hunt, and 4th with ✈✈✈ Galactic Trendsetters ✈✈✈.


I flew into MIT on Wednesday, two days before the hunt. It turned out that we waited until the day before to get snacks, and we didn’t have access to a car on Thursday, so we decided to just buy everything at Shaw’s/Star Market. Unfortunately, we also didn’t have access to shopping carts, but luckily Max had like 4 empty suitcases lying around his room so we planned to use those. Anyways, it was pretty funny having 8 people walking into Shaw’s, buying 400 dollars worth of snacks and drinks, and trying to stuff everything into suitcases. Overall, it turned out surprisingly well because exactly the right number of people came to carry things back to hall, and the snack choice was also fine (as my team knows, my only complaint is that we didn’t have any HK Anderson peanut butter pretzels, which are far and away the best snack in existence).

I planned to sleep from 2 to 10 AM, but I woke up at 3 or so and couldn’t fall back asleep, so I paced around, read Facebook, read poetry, etc. Eventually I think I fell asleep around 7, so although I only got ~4 hours sleep total, this was 4 hours more than I got last year, which is an improvement.


On Friday morning, a bunch of us head over to our rooms to move tables around and set up the food. Somehow, we got 3 moderate-sized rooms this year, which is amazing compared to previous years (last year we had 1 large room whose windows didn’t open, which eventually got pretty awful). The windows also almost didn’t open this year, but then Theo figured out how to do it (you needed to push down before you could pull up), which boded well in terms of puzzle-solving! We go to Flour as usual, and head to the kickoff. The skit was great, and basically everyone was excited.

Early on, I spent a large amount of time adding puzzles to our google spreadsheet system instead of solving because I set it up the night before and couldn’t figure out how to give other people access. Thankfully, Jakob figured out how protected ranges worked by Friday evening, so I wasn’t doing it the entire hunt.

SPOILER WARNING: I’ll talk a little about the puzzles I worked on now, so feel free to skip to the bottom if you want to avoid spoilers. Also feel free to skip to the bottom if you don’t care about specific puzzles; this will probably be long and rambling.

I started by working on Four-Part Harmony. We were quite puzzled for a few minutes before someone decided to read the first word of each line, and then I think it was solved within 5 minutes.

Next, I joined some people who were doing Locked In and basically watched it get solved. This was a very fun puzzle, so I suggest that you try it out if you haven’t seen it.

At this point we’d unlocked the first quest, so Lucy, Nathan, and I decided to help out on Star Search. People were mostly done with song identification by then and were trying to figure out what to do with, well, all of the data. We were stuck for maybe 30 minutes-1 hour, when I had my favorite aha moment of the hunt. I was thinking of the astrology symbols, and I said something like “Hmm, aren’t there also 88 constellations, like 88 keys on a piano? Maybe we should see if there’s a canonical ordering or something….awww it doesn’t look like it.” Lucy and I then looked at the Aries keyboard, and we were like “Hmmm Aries is pretty early in the alphabet and it’s on the 7th key in this keyboard, I wonder what’s the position of Aries in the alphabetized list of constellations?” Then we looked it up, discovered it was also 7, went “OHHHH NOOOOOOOOO,” and the puzzle was solved fairly soon afterwards (though we had some issues due to being bad at counting).

Some people were stuck on Heirplay, so we looked at that next. Again, we were stuck for quite a bit, and for a long time the only thing we liked was CRAM->CREAM in the second group. We tried lots of incorrect things like transforming each group in a different way, but at some point, Patrick saved the day when he turned CAT+BAND into BATDANCE and saw that it was a Prince song. Then, we all understood what the flavortext meant.

After that, I joined a group of people who were all looking at Basic Phrenology, which was stuck on the final step. I didn’t help at all, but I’m mentioning this puzzle because when someone finally figured out what to do, it was pretty amazing, and you should try it yourself/read the solution to find out what it was.

Next I worked on Repeated Punishment with Nathan, Lucy, Stephanie, and others. I think we figured out what to do immediately (Nathan remembered a 2013 Mystery Hunt puzzle that used the same source material) and it was done very quickly.

I spent the next ~2 hours working on A Beauty Cold and Austere in the second quest with Lucy, Jon, and others. The puzzle provided parametric curves which looked like public art somewhere on MIT, and each artwork corresponded to one of the statements at the bottom, from which you could extract the parameters, which converted alphanumerically to the answer. We spent way too much time failing at graphing these, because it seemed like no one had Mathematica on them (no more free licenses from high school math competitions lol). We manually transcribed some of them by hand and tried to stick them in WolframAlpha, except WolframAlpha sucks. Jon was able to plot some of the simpler ones in Sage, except we couldn’t identify any of them. Someone had a laptop which had Mathematica, except when I tried copy-pasting the first equation, it failed at graphing it. Right when everything was looking bleak, I tried another equation in Mathematica, and it actually worked and we immediately identified it as the red sculpture on the Stata lawn, which I now know is called Aesop’s Fables, II. Jon and I walked over there to find out which beam had the signature on it, and we were able to deduce that the first two letters of the answer were S and T. Then, Damien found a picture of the butterfly sculpture, so we now had ST??S??????. I guessed STRESSED OUT from Onelook, which was incorrect. We looked closer at the constraints on the parameters and saw that the third letter had to be less than the fourth letter, the eighth letter was one of {F, G, H}, and the ninth letter was one of {C, D, E, F, G}. Armed with this knowledge, we guessed ST ELSEWHERE, which was correct! Yay for Wheel of Fortune.

The third quest was open by then, so I looked at Changing Rooms with Leon, Rahul, Catherine, and others. We slowly made our way through the cryptic, which turned into a Star Battle and a LITS puzzle at the end, in an extremely impressive feat of construction (you can read the solution for details). Along with Star Search, this was my favorite puzzle of the weekend.

Next, I looked at Listicle with Leon, which was stuck after a bunch of the -ical words were identified. After trying some things for a few minutes, I read the flavortext some more, and said something like “Isn’t there that one song from Cats which lists a bunch of adjectives like this?” Luckily, that turned out to be correct, although it was unfortunate that we didn’t use the “google everything you have together” strategy earlier. I think in the next 10-20 minutes or so, 3-4 other Thespians puzzles were also finished, and the Thespians meta was soon solved.

I hadn’t done a single logic puzzle yet, so I was happy to see that Stackuro was open, and I got to work on it with Lewis and Brian S. We quickly figured out the gimmick, and the puzzle went fairly smoothly; I think we finished in about 40 minutes. There was one minor bump where we thought we had a contradiction, but then we realized that 84 could be factored in more than one valid way. Overall, I thought the solve path was very slick and I’d highly recommend this to people who like logic puzzles!

Around this time (midnight-ish), our team also solved the last two character metas and had the “Big Bad Battle” encounter, which was a lot of fun. To summarize how it worked, we had 6 people representing the party members moving themselves on a grid of wooden hexagons. Each turn, the evil sorcerer Mystereo Cantos would use some attack, to which one of the party members had to thematically respond with their special ability a.k.a. the solution to their metapuzzle. Then, a die was rolled to determine how many thematic trivia questions they had to answer in 60 seconds, and if the number was successfully met, everyone could remove the hexagon they were standing on to reveal something beneath. At any time, we could try to shout out the final answer, which was presumably on the grid underneath the hexagons.

There were two pretty great things that happened during this encounter: first, in one of the rounds, we rolled a 1 and had to answer 10 questions in a minute. We ended up barely succeeding, which was pretty exciting. Second, early on we thought that the lines underneath the hexagons were making runes, so various people were trying to look up the runic alphabet and translate them as they were getting revealed. After a decent chunk of the grid was revealed, Alejandro suggested “HIVE MIND” as the answer, which turned out to be correct. When asked how he got it, he said something like “It’s not runes, it’s just a really edgy font!”

I helped finish off location.location.location, a very cute puzzle, and then some of us tried looking at the Crafty Criminal meta now that we had 6/10 answers. Someone noticed that the second words of the answers only had letters in BLACK or WHITE, which suggested mastermind given that all the first words were 6 letters long. Lewis figured out the final answer; in the end, I think the time from start to finish was ~20 minutes which was pretty good.

It seemed like the Broken Bridge meta needed more answers, as we were at 7/16 solved, so Patrick Y and I decided to look at Altered from the Original together, which had a good amount of data gathering done but was stuck. We suspected that there might be some property that all the songs shared, and we quickly found that each of them was based on a classical piece. Now it seemed that all we had to do was index into the composers by length of the clip (the earlier group had noted that clip lengths were all integers) and sort by the pitch shifts, which seemed to be unique. However, this didn’t work, and we suspected that it was because some of the pitch shifts on the sheet were incorrect. Luckily, around this time Ian came over and was able to help us listen to the songs and identify shifts. We indeed discovered several mistakes, and once those were corrected we extracted the answer. Checking your work succeeds again!

A couple of other Broken Bridge puzzles were also solved in the meantime, bringing us up to 10/16, so Jon and I took a shot at the meta. We noticed that each answer was related to a 4-letter word and put together some word ladders, but got stuck because we thought there would be 4 4-letter word ladders, instead of one giant one as it turned out. At about 3:30 AM, I decide that I’m tired and need to go to sleep, but I realize I can’t easily get into East Campus because there aren’t any MIT students left. Luckily, Jon’s room at the Marriott had two beds and he was also heading to sleep, so I was able to go with him. I went to bed around 4:30, shortly after reading that the coin was found.


I woke up at around 9:30 AM, headed back, and found out that we had solved all the metas except for Modest Minstrels, which basically everyone was looking at now. From checking the spreadsheet revision history, it looks like Curious Cube was solved at 4:45 and Maniacal Merchants was solved around 5:45, followed by Broken Bridge at 9:30 after we had 13/16 answers in the round, and Woeful Warlord at 10:00. Patrick X told me after the hunt that the last-unlocked Woeful Warlord puzzle, Hopping Lock, was surprisingly easy: looking at the spreadsheet history, I see that it was unlocked at 9:14 AM and solved at 9:24 AM, which corroborates that statement. 😛

I spent the next few hours on the Modest Minstrels meta: I double checked the modes/scale degrees of the music clips, and tried many different ways of extracting, but nothing seemed to work. At some point we decided to use a hint, but it turned out that we didn’t read the rules carefully and you couldn’t use hints on metas, oops. I also noticed that all of the puzzles in the round were in alphabetical order except for Elf/Dwarf Brawl, which was a little strange, so I put in a contact request asking about that. HQ responded and said it was a mistake and that it would be fixed, which led to another contact request asking if the clips were still in the right order, to which they said yes. At around 11:30, Ben, Josh, and I decided to go to the Student Center for lunch; on the way, Ben got another call from HQ saying that the clips were actually in the wrong order. Once that was fixed, the meta was solved pretty much immediately, though we were very impressed that teams were able to solve it despite the error, which affected 6 out of 18 letters for us.

Finally, we got to do single-team versions of the last two events in order to unlock the Foreboding Final Fortress. I skipped the Strength/Dexterity one to eat lunch, but went to the Wisdom/Intelligence one, which was a fun twist on pub trivia.

The final encounter was a lot of fun, though I won’t describe it in detail because other people have done that and this is getting quite long. The runaround was short and sweet, and it was made pretty great by Alejandro reading each step in his best “epic voice” as we went along. The only slightly disappointing thing was that at the end, we didn’t find a coin but instead a “coin-shaped hole.”



Our team spent the rest of the afternoon playing party games in the Jackbox Party Pack, like Quiplash and Drawful. This was a lot of fun; some of my favorite responses included:

  • For a prompt of “Fastest way to become a millionaire,” someone wrote “Move to Zimbabwe”
  • For a prompt of “How to know when you’ve found the one,” someone wrote “When you say WHOOSH and they respond NEOWWW” (a reference to the pronunciation of the airplanes in our team name)
  • For a prompt of “A bumper sticker you’ll never see: ‘Honk if you’re ____'”, the two responses were “A goose” and “Blind.” Maybe I’m a bad person for laughing at the second one.
  • For a prompt of “What you will bequeath to enemy when you die,” I wrote “50/50” and Patrick Y wrote “A puzzle by Derek Kisman.”
  • For a prompt of “A new name for bananas,” the two responses were “Bananas 2: Attack of the Clones” and “Bananas 2: Revenge of Jafar.” I have to stress that everyone writes their answers independently at the beginning of each round.

A bunch of us got dinner at Thelonious Monkfish, and all I can say is that any dinner with Amol Aggarwal is an awesome dinner.

On Sunday, a bunch of us met up again in HQ to play more games: Charles brought several board games, and more Quiplash/Drawful happened. Several of us also tried making our own puzzles for fun, which eventually grew into the Galactic Puzzle Hunt.

Finally, this last anecdote is not related to puzzles at all, but I figured I should talk about it since it was one of my favorite moments of the trip: for some background information, our hall has had this silly tradition where people schedule late-night IHOP mobs ridiculously far in advance. True to this, on March 1, 2016, Nathan and Amol sent out an e-mail scheduling an IHOP trip for January 17, 2017 at 12:17 AM. Of course, this ended up happening, and we got a group of 15 or so people walking to Harvard Square at midnight. When we arrived, we encountered a very pleasant surprise: they had a promotion where you could get infinite pancakes for something like 6 dollars! And then, to pile some absurdity on top of an already absurd situation, one of the options on the regular menu was 5 pancakes for 7 dollars (!!!) I ended up eating 9.


Our team was pretty big this time around, and it might have been our largest team yet: I think we had close to 60 on-site solvers, with another 10-20 remote solvers. I think we’re at a pretty good team size: there’s a tradeoff where as you get larger, your team can get through more of the hunt and have a better chance of finishing, but it can also feel more impersonal and you personally see a smaller percentage of the puzzles. Right now, I feel pretty confident that our team is capable of finishing the average hunt, and I wouldn’t want to grow much larger for the reasons above.

Our team finished 4th, which was a pleasant surprise given that we usually finish around ~10th place. I think there were two main reasons for this: 1) We were larger this year and just had more experienced puzzlers in general, and 2) We are perennially awful at metas, but the metas this year were easy enough that none of them really stumped us, except for Broken Bridge (and even then, we had the correct idea but needed more answers). I actually think that we could have finished earlier if we started working on metas earlier: unlike some other teams, we don’t have anyone devoted to working on metas, so they usually only get looked at once we get a sizable number of answers and people decide that it’s probably solvable.

Overall, I thought the hunt had plenty of solid, clean puzzles, and I had a great time solving with Galactic Trendsetters! I didn’t encounter a single puzzle that was unfair or overly frustrating, which is sometimes taken for granted and isn’t always the case (looking at you, Trivial Mathematics and Wisdom is Eternal). The hunt was error-free except for the aforementioned Modest Minstrels meta, so I really have to applaud all of the testing and proofreading that these puzzles went through. Of course I do wish it lasted a little longer, but I can’t complain, especially given the record number of teams that finished the hunt, which is awesome to see.

As a final note, I am awful with names, so if any Galactic Trendsetters people are reading this and have corrections, let me know.


Perhaps inspired by Dan Katz, I want to blog a little more about puzzles and puzzlehunts in the future. While making the Galactic Puzzle Hunt, we had quite a few “puzzle philosophy” discussions, so I’ve been thinking a lot about what kinds of puzzles I enjoy and I might want to write about stuff like that. At the very least, I am going to talk about how the Galactic Puzzle Hunt went.

Also, this doesn’t mean that I’ll stop making logic puzzles! I’ll probably continue my schedule of ~1 puzzle/year, though I might be inspired to write more at some point (especially if people have suggestions for what kinds of puzzles they want to see 😉 ). I did make several puzzles for US team practice at the WPC, so I’ll post those at some point. And on that note, I promise I will finish my WPC recap someday! (now that I’ve managed to finish one recap, I’m sure I can do more)

Written by qzqxq

March 29, 2017 at 4:02 am

Puzzle 23: Black Hole Tapa

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Rules (copied from the TVC instruction book): Follow regular Tapa rules. Additionally, each row/column must contain N Black Holes. Black Holes must be placed on the Tapa wall. For the purposes of surrounding clues, a cell with a Black Hole counts as M consecutive shaded cells instead of 1. Black Holes may touch each other. N and M will be given in Puzzle Booklet.

Also, in this puzzle, one of the clues has a 0 in it. I think the meaning of this should be natural, but just to be precise, the 0 must correspond to a non-empty group of black cells whose total length (adjusted for black holes) is 0.

Edited to add one more clarification: Even though the black holes count as 0 for clue purposes, they still count as black squares for everything else (black holes count for connectivity, you can’t have a 2×2 square of black holes, etc.)


Notes: Well, I suppose I’m still alive. 😛

After going to the WPC (I’m currently writing a recap and hope to have it finished at some point), I’ve been motivated to get back into making puzzles after I basically had no time at all the past year due to school/burnout. So, have some TVC practice! Although I’m not sure whether this puzzle is representative of a typical Black Hole Tapa, as M=0 is a little unusual heh.

Written by qzqxq

December 1, 2016 at 11:51 pm

Posted in Puzzles!, Tapa, Variations

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Puzzle 22: Nurikabe (pairs)

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Rules from MellowMelon’s blog: This is a Nurikabe puzzle, with a twist. Every region of unfilled cells must contain exactly two numbers (instead of one) and have total size equal to the sum of the two numbers.


Notes: After a 3 month break, and thanks to a 2-hour long physics class, we’re back. 😀 Also, there’s no hidden valentine’s day theme or anything (I didn’t even know that it was valentine’s day until I saw students carrying around flowers today, heh). The 2s are, well, for puzzle 22, and feel free to count how many 2s there are.

On another note, I might post a more detailed mystery hunt recap sometime. Out of the logic puzzles I remember, Portals was amazing, Agricultural Operations was cool, A Regular Crossword was cute, and Random Walk was okay but had lots of trial and error. Palindrome was an awesome team to solve with, as usual!

Written by qzqxq

February 15, 2013 at 2:35 am

Puzzle 21: Skyscrapers Fillomino

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Rules (from the Fillomino-Fillia 2 booklet): In addition to the usual rules, the numbers in the grid should be treated as building heights. Numbers on the outside of the grid tell how many buildings are visible when looking from that direction. A building obscures all buildings behind it whose height is equal to or smaller than itself.

Notes: This puzzle is brought to you by the numbers 1, 2, 3, 4, and 5.

If you haven’t done Fillomino-Fillia 2 yet, there’s still time! You can still start the test any time in the next 3 hours or so. And even if you don’t plan on competing, you should definitely do the puzzles afterwards, because they are amazing.

Written by qzqxq

October 29, 2012 at 9:16 pm

Posted in Fillomino, Puzzles!, Variations

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