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Unanswered Questions

39
votes
1answer
3k 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 ...
24
votes
0answers
696 views

R.H.P.C. crossword puzzle

This is an entry into the Fortnightly Topic Challenge #36 I got a ticket to the Red Herring Puzzle Club in the middle of the street. There was just a guy giving them out, like some advertisement ...
21
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 ...
18
votes
0answers
969 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
0answers
334 views

With Apologies to Robert Frost

I heard this from an elderly German gentleman with a strong accent. At first I thought he was reciting a Robert Frost poem, but then the last line confused me. Some see de earth vill end times four,...
16
votes
0answers
2k 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
1answer
699 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 ...
13
votes
0answers
807 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: ...
12
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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, ...
11
votes
0answers
936 views

You don't need any hints

One enigma in trying to develop entertaining puzzles: Is it better for it the challenge to be very obvious and bubblegum? Maybe it should attempt to be virtually inconceivable? It is certain: A blend ...
10
votes
1answer
278 views

What a weird final exam

someday, some math teacher decided to test the logic deduction capacity of the class consists of 32 students. When the class began, he showed a letter to each student between A to E and said: "There ...
10
votes
0answers
513 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 ...
9
votes
1answer
101 views

Solemn, Unhurried Enigma

Scan me, seeking hidden worth. Uncover prizes, gems unearth. Envision! Witness! Look and find! Make mazes, paths. Unmask, unwind. Any means and any acts. Investigate wild wacky facts. ...
9
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0answers
796 views

Decrypting the Key

So I've been trying to solve this Riddle called "Phage is Spreading.." ...
8
votes
0answers
308 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, ...

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