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Unanswered Questions

109 questions with no upvoted or accepted answers
45
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 ...
25
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 ...
20
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 ...
16
votes
0answers
5k 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 ...
15
votes
0answers
810 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
944 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
votes
1answer
609 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
393 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
0answers
250 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, ...
9
votes
0answers
544 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
873 views

Decrypting the Key

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

Who am I? A puzzle in parts

I am one of four brothers, we make a foundation in some way we are native to every nation if one is kind, the other is not if one is a little the other is a lot from what you give i will take only 1 ...
8
votes
0answers
203 views

Determining the meaning of a challenge coin

I saw this rather cool looking challenge coin the other day, and I was wondering what the associated binary on the back of it means, as it isn't standard ASCII. I'd appreciate it if you all have any ...
8
votes
0answers
1k views

REALLY important days in history

@Z. Dailey asks a mathematical puzzle Important days in history... and to come! with a series of dates in years 1973, 1978, 1983, 1992, 2005. My puzzle asks the question: What is the previous date in ...

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