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Questions tagged [cipher]

A cipher is a simple method of modifying messages to make them unreadable, but still possible to recover. Common ciphers are Caesar, Vigenere, Atbash, and several types of substitution cipher. Other ciphers include polynomial ciphers such as Playfair, Foursquare, etc.

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6
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3answers
312 views

How to Make Non-too-broad Cipher Puzzles?

// I'm not sure whether this is better to be asked here or on meta. Unfortunately, many people (or at least my friends) agree that puzzles are plainly just "random guessing" in a sense that they ...
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Image riddle good luck

You will have to decode a secret word from this image: And then use a cipher to combine the word and decode the encoded message below Again, good luck! Encoded Message: Zeyd Iuhpchhpp
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1answer
313 views

An old inscription

A tribe that lived here centuries ago called the Rreiorclskl had been very mysterious until now: The only things known about them were that they liked poems, math and puzzles. However, very recently, ...
6
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2answers
643 views

A Magical Cryptography Puzzle

The following is the first and second sentences of one of my favorite (and fairly popular) fantasy books encoded in a cipher I created a few years ago. I'm quite certain it's breakable, but hints/more ...
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6answers
9k views

Four boys are playing football and one of them breaks a window

Four boys at school are playing football and one breaks a window. No one owns up to doing it but someone gives the teacher an anonymous note saying: hE iS thE CuLpriT? The four boys were: ...
34
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1answer
1k views

A Morse Conundrum

Yesterday, I intercepted a message encoded in Morse code, but, because I was extremely tired, decided to wait until today to decode it to plain text. However, when I looked at the piece of paper I had ...
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3answers
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Same Riddle Different Answer: I am both lock and key - who am I?

NOTE: Though the body is identical to I am both lock and key - who am I?, a different answer is expected, and thus this is not a duplicate. Cyrnfr qb abg pybfr guvf dhrfgvba.Thanks! Enter! Small or ...
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1answer
115 views

PSE x Wiki x World: How can it be?

The following is a encoded first line from a Wikipedia page. Your task is to decipher it. Enjoy! 239#27#682 372#52#41#599#995 354 856 227#886#244#82#94 252#681 672#61#32#239#246#673-376-599#46#597 (...
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5answers
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What's for dessert?

Another puzzle, yay! What do I want for dessert? An element, a blue liquid you breathe. The end of a sentence. wgpz tzggjr wgvxf bmzzi mzy It's three til' 4, plus forty more. Hint:
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1answer
183 views

Alternating Audio Waves

Try solving this cipher from these strange memos: Memo 1 Welcome Comet, today's Thisbe plus Russell here! Memo 2 Reading outlaws loudness. Memo 3 Retro memo: Berlin today upheld voting ...
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2answers
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A Fun, Fantastic, Phonic Cipher!

An old friend of mine recently sent me an email. Being a linguist, he always finds creative (read: annoying) ways to use his words to baffle me. After about five minutes, I usually just give up. ...
6
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1answer
466 views

Is there a hidden message this old Polybius listing?

I recently watched this video about the mythical arcade game Polybius. It's a well-crafted investigation that thoroughly debunks the myth, but there's a segment in which the investigator suspects a ...
4
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1answer
233 views

This picture has some hidden message. What is it?

This picture was uploaded for the Olympiads of Medicine, from Porto. While the answer might be in portuguese, I don't find it likely. I tried some Caesar Cyphers, I assumed the colours represented ...
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1answer
169 views

someone sent me this cipher. what does it say? [closed]

someone sent me this cipher by email."gnkx bzud skoo xgzfg dzxh, tjg kg kx tkbbdf gnzy hlj uzh iyls. ky gnkx bzud hlj ezy nzrd gdzux. hlj skoo td fzekyb lgndfx. gnd ulfd hlj vkyc gnd ulfd hlj iyls."I ...
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1answer
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Trying to crack a code [closed]

I am trying this string set of puzzles. The last puzzle to do, began with 055 055 055 055 ...…040 056 055 055 055 055 which translated to: 77777(77777(877 …… 77(87777(87777 But I cannot work out ...
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1answer
472 views

There is a secret message in the picture #3

This picture is from the 50 trillion dollars challenge from the free ebook "Muko and the Secret". This one is already solved by a reader.
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3answers
586 views

Where is the money?

When I was just a little kid my parents died in a terrible accident, and I was left alone in the world. When I reached the age of 18, I received an envelope with a letter that read the following: ...
0
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1answer
125 views

Need help to decipher this encrypted text

I am relatively new to deciphering texts and I have the following ciphertext: xbt ufp ekyzkikn dt nkojvhk? e ndmr jfo nggv du kwjt gun pjv. I tried Caesar Cipher but to no avail. It would be ...
6
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1answer
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Crack Me 01 - Crypto Riddle

This is the encrypted message: xy}v"|y#xu|$|&a+&y}vsa*pppp*fprppp"prpp"upppzpqppp*"vptp|at~!*+p)~yr%"&t"&y}vsa* This is a riddle in parts, follow ...
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3answers
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Is there a secret message in the first decimals of PI?

Is there a secret message encoded in the first decimals of $\pi$? Source: Vi Hart
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1answer
331 views

The Research Paper

So, one of my friends is a teacher, and, for one of their recent assignments, one of the teacher's students turned in this: hkszocukgdxkcmvkuhgcskflfpnwebqhttbxhpwokywiyevvfohlgzqklw 6n1 ...
18
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1answer
402 views

In Time or out of Time, that is the question

Brushing away the tree roots hanging from the ceiling I realised that the unicorn had stopped. “I will not go further,” he said in his deep, rich voice, “you know the prophecy. There is only one who ...
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0answers
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Solve it… Uncover the mystery!

One of my friend, who is really too good with cyphers and puzzles challenged me to solve this one. I think it reveals a name, or date or some information with which he can surprise his friends. That's ...
5
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1answer
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A long but relatively easy cipher - Clue Two

<-- Previous clue After submitting your answer in the email, you wait eagerly, on the edge of your seat. After about five minutes, your response comes back. It says: Wonderful. You have ...
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4answers
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Riddle Number Six

Fiddle diddle diddle, time for another riddle. This is another little puzzle I've concocted for you all this evening. The scenario is this: You awake in a small room with only one door. The door is ...
3
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Riddle Number Five

I feel as if my challenges are a bit too extreme for many, so here is a more simpler conundrum to solve. The cipher used is the same as the answer to this riddle: When is a cipher like a person who ...
3
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2answers
375 views

Puzzle hidden in Hannah Fry's Hello World

Hanna Fry announced today that she hid a puzzle in the cover of her book—via twitter The initial clue seems to be a binary encoding of some ASCII. I was hoping to start a thread towards finding a ...
5
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2answers
265 views

Riddle Number Seven

Seems as if I've left you all a little puzzle for today. It's a simple cipher that I'm sure you can all deduce. Everything you need is provided in the image. Have fun everyone!
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3answers
378 views

Who is John's favourite painter?

John being his usual self forgot the name of his favourite painter. He went to the Oracle for assistance but inadvertently walked in on her while she was busy eating pie. Angry at the interruption, ...
3
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2answers
357 views

Riddle Number Three

Time for a challenge! Here, the riddle is encoded using a specific cipher. You must decode the numbers and answer the riddle correctly to solve it. Good luck! 83191143|2367|02|41026731|434771|02|...
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1answer
136 views

Another challenge for you guys

Ciphertext: ...
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1answer
138 views

Little challenge for y'all

Ciphertext: ...
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4answers
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This is important. I need you to listen…

Look, you don't know me. We've never met. But, like I said, I need you to listen... I had the most disturbing dream the other night... Woke up in a cold sweat and couldn't get back to sleep. It wasn'...
9
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1answer
338 views

A chess game with odd moves?

A friend and I like to play chess regularly. Like me, he is a lover of a good puzzle, which is what drew us to the game. The thrill of finding a checkmate in a board riddled with pieces cannot be ...
6
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2answers
196 views

Sukarno's Holocene Extinction Discovery

You are a renowned paleobiologist who travels the world and evaluates recent discoveries. You recently were contracted to fly to Jakarta University and check in with one of their researchers. You ...
7
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2answers
534 views

A hexagon cipher

Note: This question looks like spam, but it isn't. All the "spamminess" is intentional and crucial to solve the puzzle I have received an email and this was attached to it: What does this mean? ...
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2answers
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Monoalphabetic Game Theory

This is a third puzzle from the Monoalphabetic Equation series, you can check out the previous one here: #1, #2. Last night, I went over to my friend's house for our monthly game night. After we ...
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2answers
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Find the number [closed]

Ocz vinrzm dn ji ocdn kvbz Find the numbers
3
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1answer
152 views

Looking for Cipher Help

This cipher has me vexed. FOOTOOLTLTLBDCLOLTLTJBFTOCFTOOOCDC. There appear to be too many Os(and no other vowels) to be a transposition cipher. The coindidence index is 14.75, which is quite high, ...
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2answers
2k views

Mysterious email message

Today I found something quite interesting in my email. An xml file with this puzzle: -|- |-| 0_ |\/| 0 0 |\| | § |_ | -|- Can you solve it for me?
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3answers
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Cipher: No idea where to begin

Ok so I have this cipher which I have no idea what to do with. I have tried most substitution ciphers I know of and still have no idea. Brute forcing with frequency analysis also yielded no results. ...
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1answer
483 views

In a certain code language if CONFIDENCE is coded as FGPEGEQPHK then how will PERFECTION be coded in the same language [closed]

A certain code enciphers CONFIDENCE as FGPEGEQPHK. What will it do to PERFECTION?
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2answers
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How do I go about solving this cipher?

A friend and I signed up for a pay-to-play D&D campaign some time ago. Near the start of the campaign, our characters were given a puzzle to figure out. We're approaching the end of the game in a ...
5
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1answer
353 views

There is a secret message in the picture #2

There is a secret message in the picture, can you find it? This solution is also a clue (how to solve) to the previous one - There is a secret message in the picture. This picture was neither used ...
5
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2answers
691 views

There is a secret message in the picture

There is a secret message in the picture, can you find it? This picture is from the 50 trillion dollars challenge from the free ebook "Muko and the Secret". This one is already solved so I hope I do ...
6
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1answer
346 views

Riddle of Alschen

In Alschen, in 1999, a boy woke up on a nice morning only to discover a riddle on some paper under his bed. He took it to his mother who was shocked. His mother then showed the riddle to all of his ...
4
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2answers
929 views

Find the cipher algorithm and decode the message

Sam is a computer expert. He works in a Security Company. His son Tim just turned thirteen and is new to C++ programming and ciphertexts . He decides to write a C++ program to make a cipher algorithm. ...
4
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1answer
232 views

Substitution cipher for your amusement - a programming challenge

The 'message' below is a substitution cipher. It is a fun challenge to write a computer program to read in the file and count up the letters and then use expected letter frequencies to translate the ...
19
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1answer
597 views

Monoalphabetic Geometry

This is a second puzzle from the Monoalphabetic Equation series, you can check out the previous one here. A set of letters has been replaced by $a$, $b$, $c$, and $d$ and one symbol has been replaced ...
15
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8answers
1k views

Defuse the Bomb

You suddenly wake up in a room. You have no idea where you are, who you are, and why you are here. A look around yourself shows you to be in a room almost entirely made of depleted uranium other than ...