2024 April Fool's Puzzle Competition Summary & Solutions

This is a rebus puzzle.

The symbols are the japanese character れ (re) and a bus.

The answer is 'rebus'.

A sentence made up from ISO 7010 hazard and safety signs. There’s a lowercase variant (mandatory signs) and an uppercase variant (prohibition signs). Each sign stands for a letter of the alphabet. The sign P001, for example, stands for 'A', and the sign M004 stands for 'd'.

The sentence is “You Wouldn't Believe Me If I Told You That The Key For The Next Level Is Really Weird”

The answer is "ReallyWeird"

Snake picture thanks to Colleen O'Dell, aka StarGlade.

The lost picture poster has 10 secret messages hidden in it.

1. The filename, U2hhbWlyIGNhbid0IHJlYWQ= decodes as base64 to Shamir can't read
2. In the EXIF of the JPG is hidden the comment Shamir is actually twin brothers
3. At the end of the file is the plain text string Shamir is three kids in a trenchcoat
4. (error) The four stripes at the bottom of the snake are colored. Their actual hex values are erroneously one off in some cases due to JPEG compression. Their hex values should instead have been: #416469 #486174 #65734B #697474 #656E73. In ASCII, this hex decodes as AdiHatesKittens.
5. Along the snake’s top belly stripes is hidden morse code: ... .... .- -- .. .-. / .-- . - ... / .... .. ... / -... . -.. decodes as SHAMIR / WETS / HIS / BED
6. Overlapping three sets of mystery glyphs reveals the text Adi is the crown prince in disguise
7. Written very small in grey text on the snake’s tail is Shamir is afraid of mice
8. Hidden in dark blue dots in the snake’s right eye is the text HeIsPregnant. (a reference to a previous year's goldbug puzzle)
9. The snake’s speech decodes in binary as: ImHisPetSnake
10. The snake's speech has groups of S's separated by spaces. The group lengths decode to letters (A=1,B=2): Adi Shamir’s

Note: Shamir’s Secret Sharing is a method invented by Adi Shamir to share a secret using (say) any 4 out of 10 messages.

Who is S.S.S.S.? It’s this snake spilling all of Adi Shamir’s deepest secrets.

The key is "Shamir'sSecretSharingSna[ke]".

The player is thrown into a text adventure with a series of passages. Hidden in the passages are 5 shapes drawn on the floor, 10 plaques, and a waiver.

The layout of the passages is as follows:

                        [H]
                        [ ]
                        [ ]
         [D][C][ ][ ][ ][ ][ ]
            [ ]         [ ]
      [G][ ][ ][ ][ ]   [ ]
   [Z]      [ ]
[P][ ][ ][ ][ ][ ][ ][ ]
   [ ]      [ ]
   [ ]   [F][ ][ ][ ][ ][ ][ ]
   [ ]      [*]
   [ ]
   [A][ ][I][ ][ ][ ]
         [ ]
         [ ]
   [M][ ][ ][ ][ ]
         [ ]
         [ ]

You start in location *. The hallways each have a plaque the the top or left end of the hallway.

In addition, you have a waiver in your inventory, which starts:

MINISTRY OF PUZZLES RELATED TO THE SURNAMES OF IMPORTANT PERSONAGES: ACCIDENT WAIVER...

The map forms a crossword, the answers of which are last names of interactive fiction authors. Clues are given in the plaques, and the first letter of the game is given in the hallway letter.

• C, Colossal Cave Adventure, Crowther
• D, Dunnet, Schnell
• H, Hobbit, Megler
• F, 1893: A World's Fair Mystery, Nepstad
• P, Planetfall, Meretzky
• I, Inform 7, Nelson
• A, Anchorhead, Gentry
• M, Amnesia, Ditsch
• Z, Zork, Lebling
• G, Galatea, Short

The filled-out crossword becomes

Read in order the dot, line, triangle, square, and pentagon (1, 2, 3, 4, 5). This spells out the answer, 'prose'.

100 assorted images of Mt. Fuji were shown on the webpage.

This is a reference to One Hundred Views of Mount Fuji, a series of three gorgeous ukiyo-e books by Hokusai.

The answer was 'Hokusai'.

The text given looks like base-64, but actually can't be decoded as anything interesting using base64.

Instead if you encode it in base-64, you get the message THE2MmM4aG1CWWordSs1NkRYPT0=, or "the two magic words in crypto".

The answer is the ciphertext of a 1977 RSA challenge, "The Magic Words are Squeamish Ossifrage".

The key is 'SqueamishOssifrage'.

The key insight in this puzzle was to make a list of everything still at the party, in the order it arrived:

1. a small alpha bear (a little bear, but with real Alpha vibes)
2. a small dog (this cute lil dog)
3. a belt (some huge guy tracked down the party, but he left after he got really drunk and his pants fell down)
4. a cross (A priest came earlier chanting latin, real old-school fundamentalist type. But Bacchus kicked him out. Took his cross and burned his bible too.)
5. an Ancient Ethiopian queen (that chick over there is some kind of royalty in Ancient Ethiopia, she’s been bragging about her kid for hours)
6. a musician's instrument (The musician was pretty famous but he left without his instrument)
7. Half of Bacchus’s hot nurses
8. You, the answer to the puzzle

The party guests are constellations:

1. Polaris (Alpha Ursae Minoris) - a little bear with alpha vibes
2. Canis Minor - a little dog
3. Orion’s Belt - a giant tracker’s belt
4. Southern/Latin Cross (Crux) - a cross
5. Cassiopeia - Ancient Ethiopian royalty
6. Lyra - a musician’s instrument
7. Pleiades - half of bachus’s nursemaids, the Nysiads

Polaris has one star, Canis Minor two stars, and so on up to the seven stars of the Pleiades.

You are the most famous constellation with eight stars, Orion, back for your missing belt.

The answer is 'orion'.

The video appears to be static, but only certain pixels change. Staring at the outline or using an image diff tool, it's possible to see this shape:

Viewing the image at extreme angles, the shapes flatten into the words:

• April
• 21
• MMVII
• Bhutan

On April 21, 2007, Bhutan held a practice election to teach people how democracy works, before their first real election.

The answer was 'mockelection'.

Several hints should point the player to the relation to molecular biology:

• the spiral resembling a strand of RNA;
• the colors in the initial clue pointing to the hex colors in the HTML code, namely amber, ochre, opal and umber, which stand for the three RNA/DNA stop codons;
• the hint “don’t be a Sherlock” pointing to James Watson.

Each “pearl” in the spiral represents one base in the RNA strand, where the HTML element class names give hints on how to map element colors to complementary base pairs (A, A inverted = U; C, C inverted = G). Reading the strand in standard 5-to-3-end direction yields:

(5) UUYAUMUUA AUGGCBUGGGCDMGRGACUGA CAYGC AUGGAAGAYAUMACSAUUAACGGVUAG AC AUGUGYMGGAUWUCKCCHMGAUAA UAUUUUAACGUUU (3)

(significant parts in blue, actual message parts underlined).

There are three significant substrings, each starting with an AUG triplet (start codon) and ending with one of the three triplets for stop codons.

Beside the specific bases A, C, G and U there are some parts of the string given as degenerate base symbols which represent several bases. The player has to replace those by matching concrete bases.

Translating all significant substrings of base triples into amino acids and taking their single-letter short codes gives the three words “AWARD”, “EDITING” and “CRISPR”, hinting to Nobel Prize winner Emmanuelle Charpentier (together with Jennifer Doudna) for the CRISPR gene editing technique.

If read in the wrong direction, the string starts with the message "FAIL<stop>".

The answer is 'EmmanuelleCharpentier'.

The game was similar to tetris, with pentominos (5-square tiles) instead of 4-square tiles. The same tiles always fell each game, in a repeating loop.

Pentominos have a couple standard naming schemes.

According to one common scheme, the tiles falling are called: I, N, F, I, N, I, T, Y, L, U, P, I, N, (repeats)

The answer was 'infinitylupin'. (lupin is a flower)

The letters of ankȯö_eidmc can be unscrambled to read kȯnami_cöde.

The konami code, popularized by Contra, is a common cheat code. In Contra it gave you 30 extra lives. The code is 11 key presses: Up, U, Down, Down, Left, Right, Left, Right, B, A, Start.

11 keys is the same length as kȯnami\_cöde.

Note: The puzzle was created in Brick Link

The puzzler is presented with a comic story about a young Thor and his lively day. In each panel scene, one norse Futhark rune is hidden.

The hidden runes are from the long-branch Younger Futhark alphabet, which can be concluded from the ᛅ rune in scenes 2 and 6 which is only available in this specific runes alphabet. The theme also gives a hint, as long branch runes were primarily used in Denmark.

In the scenes the following runes occur in order: 1. A ᛏ rune is formed by the ducklings in front of Thor taking a bath. 2. Thor is engraving an ᛅ into the runestone behind the school class. 3. The weapons on the ground form a ᚱ next to the fighting arena. One of the posts of the shed behind the pizza baking place looks like a ᚴ. 4. The path in the middle of the garden has a ᛋ-shape 5. There’s an ᛅ in the pattern of the floor in front of the safe. 6. The tree on the right looks like a big ᛘ. 7. Thor and Sif are watching a bunch of dragons forming an ᚢ. 8. Another ᛋ can be found in the shining stars between the alien and Thor.

Combining the runes gives “ᛏᛅᚱᚴᛋᛅᛘᚢᛋ” = “DarkSamus”, one of the main antagonists from the Metroid video game series.

The answer is 'DarkSamus'.

The player is presented with a website. It says "Shrek: There's a lot more to ogres than people think.", a line from the Shrek movie. There is a picture from the same scene.

As the player progresses, they must decrypt each layer of the puzzle, while seeing more quotes from the Shrek "Ogres have layers. Onions have layers" scene. Each layer is named after a "Layer", or episode, from the Serial Experiments Lain anime.

Clicking "View source" reveals this comment:

Shrek: Ogres are like onions!

YNLRE 1: JRVEQ

Qbaxrl: Gurl fgvax? Fuerx: Lrf... Ab!

GRSMEIVtZwbtE0yFGSZXPxEiozgyrGbtG2tfVUEbMKxtoJSeMFO5o3HtL3W5CjbXFTyhqQbtq2uuqPOfMJ5aqTttnKZtqTuyVTAiMTIxVT1yp3AuM2H/PtcZYPkjp3x6oHk6oaLmM3cg4cFXrUu4rUu4DKy0pv7vyVcOpzqarat1oF5fo3u4rUu4rSyinT8hJIqdnF5knzclp3yerUu4rUu4EKIyqF5WVJq04evkrJL1rz1vrUu4rUu4rSWfrKGvyVcAJv5gGmc6MmW6nUu4rUu4rUtmMJqcIyWhDzuGJUS0oaAbrUu4rUu4rQcuMJ5cFaSiqyygMJfloKy4rUu4rUu4HUM0W2p0p2MfGUuzpJMcp3u4rUu4rUuGMJSfMGcypw9RraS6nl5drUu4rUu4rSxaoTyhEzSeFmIlqmI6I3S4rUu4rUu4D2IfqZBbHv52pwcmnQIxMzc4rUu4rUu4FT1vqUWHD25dIaN6pzSaoau4rUu4rUuSo3WfMIquMTASYP95Z2EdrUu4rUu4rBXHvaIiMrXHvyEup2qWnP9hM3qirUu4rUu4rRE0q3p2DJA5ryqmnmEwnzS4rUu4rUu4o2yhnTkQLKA2HaMjAJ11L3u4rUu4rUuhovkcMHSuoJ5RpJcgqUc2rUu4rUu4rTg0p3E04evkqaWxI2gzoUAfpau4rUu4rUuynUEyqRShraASoUIzATc3rUu4rUu4rUyyLJuyqz5arIqxpUcupv54rUu4rUu4BaAlLKWypl5mGayyrKc14evkrUu4rUu4rR91qTyeq3xhoIIkAzH2ozA4rUu4rUu4nT5mpzI5nF5loKqbpzAmrUu4rUu4rUtX

Running the ciphertext through ROT13 gives

LAYER 1: WEIRD

Donkey: They stink? Shrek: Yes... No!

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

The next step is to base64 decode the new ciphertext. The hint L,,psy confirms the correct base64 decoding.

LAYER 2: GIRLS

Donkey: Oh, they make you cry?

Hint: what length is the coded message?

L,,psy:mLznv3gzm┊xxxxxxAytr.┊Arggzx5m.loxxxxxxYoho.YWji.qjjrsykxxxxxxEueu.I!gt⸱yf5zmbxxxxxxxRlyt┊MZ.mO:zg2zhxxxxxxx3egiVRnBhSXqtnshxxxxxxx:aeniJqovYmek2myxxxxxxxPvt'g4sflLxfqfisxxxxxxxSeale:er?Dzqzk.jxxxxxxxY'linFakK5rw5zWqxxxxxxxCeltèR.vr:sh5dfjxxxxxxxHmbtrTCnjVp:ragnxxxxxxxEorleWadcE,/y3djxxxxxxx┊uoe┊TasgIh/ngwoxxxxxxxDtww6AcyzWsk4cjaxxxxxxxoinhlCasvRvp5mucxxxxxxxnn,ieAamnDqjmtzvxxxxxxxktstt⸱vrdWkflslrxxxxxxxehtetAnzsEluf4jwxxxxxxxyeahevngyWdpzar.xxxxxxx:srares.sNyeyzu⸱xxxxxxxOutikwy.mUq6e6ncxxxxxxxhnsreyi.rmwhrcsxxxxxxxx

The hint says to look at the length of the coded message. The ciphertext is 529 characters long. 529 = 23 x 23, a hint to arrange the letters in a 23x23 square.

L,,psy:mLznv3gzm┊xxxxxx
Aytr.┊Arggzx5m.loxxxxxx
Yoho.YWji.qjjrsykxxxxxx
Eueu.I!gt⸱yf5zmbxxxxxxx
Rlyt┊MZ.mO:zg2zhxxxxxxx
3egiVRnBhSXqtnshxxxxxxx
:aeniJqovYmek2myxxxxxxx
Pvt'g4sflLxfqfisxxxxxxx
Seale:er?Dzqzk.jxxxxxxx
Y'linFakK5rw5zWqxxxxxxx
CeltèR.vr:sh5dfjxxxxxxx
HmbtrTCnjVp:ragnxxxxxxx
EorleWadcE,/y3djxxxxxxx
┊uoe┊TasgIh/ngwoxxxxxxx
Dtww6AcyzWsk4cjaxxxxxxx
oinhlCasvRvp5mucxxxxxxx
nn,ieAamnDqjmtzvxxxxxxx
ktstt⸱vrdWkflslrxxxxxxx
ehtetAnzsEluf4jwxxxxxxx
yeahevngyWdpzar.xxxxxxx
:srares.sNyeyzu⸱xxxxxxx
Outikwy.mUq6e6ncxxxxxxx
hnsreyi.rmwhrcsxxxxxxxx

Reading the message top-to-bottom, and splitting sections at ┊, we see:

LAYER3:PSYCHE

Donkey:Oh,youleave'emoutinthesun,theygetallbrown,startsproutin'littlewhitehairs...

Vigenère

6letterkey

YIMRJ4:FRTWTACA⸱Avewy:AW!Znqsea.Caacaavnnsyimrjg.Bofrkvndsysmrzg...Lgitmhvl?Krjcgzvndsysmrzg.⸱OSYLD5:VEIWRDWEWNUmnzqy:Xmxzrsp,hsvqkldyqwvxjfzqefqwh://kpjfupe6h35j5gtkqz55ryn45mlfzyergmrz2n2fkzda3gcmts4az6cz.smzsmi.Wfgdwjuzljrunsmlybhhysjqjnjoacvrw.⸱cx

okxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

Decoding the ciphertext section using a Vigenère cipher and the 6-letter key NIONSO (or ONIONS), we get this message (splitting at ⸱):

LAYER4:RELIGION

Shrek:NO!Layers.Onionshavelayers.Ogreshavelayers...Yougetit?Webothhavelayers.

BAKYV5:HRQIEVIREZHezmyk:Kejmzec,zeiywyvkdehkbrmyqsiiu://sbwxgcm6t35w5yfxyl55eqz45ztrmqqeoyer2z2sslqs3spuff4sl6ph.ezrezq.Isypjrgmdveczfexljtuqewyvabankheo.

ok

Going from 4 to 5 requires a monoalphabetic substitution cipher. There is no trick here--the substitution is random. Decoded, you get the following:

LAYER 5: DISTORTION

Donkey: You know, not everybody likes http://hlvxcwk6m35v5efxej55osn45nmikssogeoi2n2hhjsh3hqpff4hj6qd.onion s. The quick brown fox jumps over a lazy dog.

The link given is an onion link from Tor. Visiting it shows a text file:

LAYER 6: KIDS

Donkey: CAKE! Everybody loves cake! Cakes have layers!

₿ip39 era approve eyebrow picture address other life hazard drive enforce fence rather actor motor second voice monster slice tail dolphin report dash symptom auction half arm amount melody share penalty light put grace need flat tell elegant mother random coin grace okay siege film audit exist family piano connect acoustic orange shaft craft joke lawsuit raw vacuum wise gown thrive web skate level tomato hunt forward bulk valley maple destroy tiger audit

11+11+11+11+11+11+11+11=8+8+8+8+8+8+8+8+8+8+8

BIP39 is a bitcoin addition which allows saving bitcoin cryptographic information as memorable english words. It encodes 11 bits as one of 2048 english words.

The given words decode as:

01001100010 00001010110 01010001010 10100100010 00000011011 10011101000 10000001010 01101001111 01000011010 01001010001 01010101000 10110010010 00000010101 10010000011 11000010011 11110101011 10001111010 11001011011 11011101010 01000000110 10110110111 00110111101 11011100100 00001110111 01101000011 00001011101 00001000000 10001010100 11000101001 10100010100 10000001100 10101110110 01100101011 10010011110 01011000100 11011110110 01000111100 10010000001 10110001101 00101101011 01100101011 10011001111 11001000000 01010110010 00001111000 01001111110 01010010100 10100100000 00101111001 00000010000 10011011110 11000100111 00110010000 01111000010 01111110001 10110010100 11110000100 11111100011 01100101001 11100001001 11111000110 11001010000 10000000101 11100100000 01101111011 01011011110 00011110000 11110000111 10000111100 00111100001 11100001111 00001111000

Regrouping to byte-size blocks, this is:

LAYER 7: SOCIETY + 🫏You know what ELSE everybody likes? + 🔥 / Bobs 🍔🍔🍔 / okxxxxxxxxx

This is the final clue. The clue parts hint at:

7 Layer + Parfait + 🔥 / Bob's Burgers

The answer is a fictional dessert from the animated television show Bob's Burgers, the Seven-Layer Parfait Flambé.

The final answer is 'SevenLayerParfaitFlambe'.

The first two blocks of letters hint to the Jupiter-C rocket numbering cipher, where the letters HUNTSVILEX map to the digits 1234567890.

Replacing all letters by their corresponding digit gives 10 integer values:

12345 67890 03662 16479 12817 32958 09155 07324 34789 29296 27465 36620

The player is supposed to find that all of them have a common prime factor of 1831.

Dividing all numbers by 1831 yields a series of numbers representing a letter of the alphabet each (1 = A, 2 = N etc.), giving the string “bigredspot”.

Combining those three hints (Jupiter + 1831 + big red spot) points to Heinrich Schwabe who made the first detailed drawings of Jupiter’s Great Red Spot.

The answer is 'HeinrichSchwabe'.

The video was an animated autostereogram (magic eye). If you've never viewed one, try facing the screen head on, and slightly crossing your eyes as it plays. A three-dimensional "cutout" may appear as you watch. Some fraction of people cannot view autostereograms. Some solvers instead used computer autostereogram decoders on screenshots.

The (non-autostereogram) video was provided as the final hint: https://ircp.link/IDkbp0

The video is Bad Apple, a fan video for the Touhou Project series of bullet hell games.

The key is "badapple".

Jörð is the personification of earth in Norse mythology, so from context (Jörð is the mother of Thor from Lego puzzle part 1, “secret addendum” and reference to Braille runes puzzle) the player has to conclude that cipher runes are hidden in the flower pots and beds grown by Jörð in scene 5 of the earlier Lego puzzle.

Each flower pot/bed grows flowers with two different blossom colors (light and dark). The number of blossoms for each color encodes the cipher runes (light color = “aett”, dark color = position in aett).

Starting at the top of the scene, going clockwise, the cipher runes are

1/2, 3/5, 2/4, 1/1, 1/1, 2/4, 2/1, 1/4, 2/3, 3/3.

Translating to Younger Futhark runes (as used in the first Lego puzzle part) with the usual first/third aett flipped using the translation table

gives the word “ᛒᚱᛅᛏᛏᛅᚼᛚᛁᚦ” = “Brattahlíð”, a former settlement of Erik the Red on Greenland.

The answer is 'brattahlid'

The clue is a recursive, fractal maze (credit to Mark J.P. Wolf).

The solution is to chart a path through the maze, which starts at (full-size) Link and ends at (full-size) Zelda. The sword starts at 3, and this number gets multiplied by 3 or increased by 1 as you pass different NPCs.

Here is one of the two common solutions: