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Unanswered Questions

43
votes
1answer
4k views

Unsolved Mysteries: D'Agapeyeff cipher

The D'Agapeyeff cipher is an as-yet unbroken cipher that appears in the first edition of "Codes and Ciphers", an elementary book on cryptography published by the cryptographer Alexander D'Agapeyeff in ...
23
votes
0answers
3k views

Binary cryptogram from a friend

My friend sent me a "puzzle" in binary, and said that there are multiple steps to solving the puzzle, all of them including decryption. I translated the binary into text and he said that was a good ...
19
votes
0answers
1k views

One 'double agent' two-step on a waltzing floor

I'm in a jam – cornered I am! – No clue 'bout where to go Here's what went down, a pretty gown Some wine, a French chateau She whispered underneath her breath "Come dance with me and ...
17
votes
1answer
895 views

An Alien Message

A spacecraft was found orbiting earth. It was not made by us, but appears to be intended to be received by us. This is a transcription of the engraving on one of its many panels: Some of the symbols ...
16
votes
0answers
4k views

The Beale Papers

The background to this one's given here: http://www.damninteresting.com/89-263-201-500-337-480/ NB: These may not be a genuine cryptograms (current thinking is that these are gibberish); but I though ...
14
votes
0answers
734 views

BFTIODFTTWKBCSC

This is my first self-developed cryptographic puzzle. I hope it is neither too hard nor too easy for you to break, and that you enjoy it. Please do not only post the answer, but also your way towards ...
14
votes
0answers
904 views

Deus Ex crypto puzzle

There is an encrypted email in the recent Deus Ex: Mankind Divided game: From the game files, this appears to be the string: ...
13
votes
0answers
1k views

Is there a more efficient way to rotate the centre pieces on the Octo-Star?

I'm looking for a more efficient algorithm to rotate the center column of the Octo-Star puzzle 45 degrees. The situation below occurs when four properly-oriented edges are next to each other, ...
12
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0answers
533 views
+50

A lumberjack unjustly captured

One day in China, a lumberjack was caught unknowingly cutting down one of the emperor's favorite type of tree. Because of this, the lumberjack was taken into captivity. The surrounding towns in which ...
11
votes
0answers
494 views

Creepy video on Youtube, with secret cipher built in

This showed up in r/deepintoyoutube: https://www.youtube.com/watch?v=j1ExfbH4Jew I've posted it around, and no one has solved it. I believe it is a cipher for a couple of reasons, at the end 26 ...
10
votes
0answers
345 views

Alternate, complex potions puzzle from HP fanfic

A long narrow room. The entrance is blocked by purple flame, the path onward blocked by black flame. On a table, the only thing in the room, are two dozen potions in opaque bottles. Half green glass, ...
9
votes
1answer
307 views

My Final Song to Riley

Entry into Fortnightly Topic Challenge #38: Reusing Information 1 This will also be my final Riley Riddle for a week or two because it is arriving near the end of the term and school is expecting ...
9
votes
0answers
511 views

Hundreds of thousands of words contained in such a small package

If you find that you are crafty you will see the answer's: ___________ CfAaEuDbLcIuHk DbBaAbEbAiEfIa JaCaEaIcIcEfIa JaCaAaEfAaEfIa BcJkAaEfAaEfIa EbIkAuEfAaEfIa EbIkAbEfAaEfIa DfAqEaEfAaEfIa ...
9
votes
0answers
838 views

Decrypting the Key

So I've been trying to solve this Riddle called "Phage is Spreading.." ...
8
votes
0answers
195 views

Bongard Metapuzzle

An entry in Fortnightly Topic Challenge #38: Reusing Information 1 A Bongard Problem is a problem where you have 6 symbols on either side of a line. The symbols on the left follow a certain rule, ...

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