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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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### Hidden Message: Code and Calculation

There is a hidden message that can be decipher from the string below. Try to figure out what does it actually says. The final answer will be in text form. ...
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### BASE jumping from One World Trade Center

The well-known daredevil, Sauren Baumgartner, is standing on the top of One World Trade Center (in Lower Manhattan) just before sunset. Following his physical and mental preparation, he calmly drops ...
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### Five puzzles in one!

This is an experiment of nested puzzles. The answer of each puzzle is necessary to solve the next one. Sometimes you have to manipulate it, sometimes you have to open your eyes (and mind). Run, to ...
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### Help me learn to speak Susan's language

Susan was born with an extreme case of the rare communication disorder, "dyscryptia", which has enthralled neuroscientists and computer scientists alike from all 6 corners of the globe. She is one of ...
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### The Hunting of the Snark: Given ciphertext and plaintext, what cipher is used?

This is a cryptogram puzzle. Below is some text; each section of the original text ('plaintext') is followed by an encoded version of that text (the 'ciphertext'). Your challenge is to explain the ...
2k views

### My friend is lost in time!

YOU HAVE TO HELP! I was time traveling with Fred last week - you know Fred, he's a nice guy - when we got separated. His hand-held automatic chronological portal manipulation and guidance unit (...
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### The Roman Crypto

This was found engraved into a stone in Roman times: And underneath, an inscription: eoofrddene·en.do·xfrtfscqqiiut·iucraeiuioceaarriocsrt·s·ieaei,imt·oesa·serism?·,· Even with only this minimal ...
874 views

### Lotus flower encryption

Decrypting this single word below, may enhance your overall health and well being. The best answer will include an explanation of the encryption steps. (An understanding of color models may be ...
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### Justice and Fairness: Part 2

A friend of yours was part of a secret society and was put on trial on 15 December 2014 without a lawyer. Alice encrypted the trial's transcript and sent it to Bob, but double agent Carol was able to ...
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### Justice and Fairness: Part 1 [closed]

A friend of yours was part of a secret society and was put on trial on 15 December 2014 without a lawyer. Alice encrypted the trial's transcript and sent it to Bob, but double agent Carol was able to ...
376 views

### Letters too close

I had a sentence, but the letters in it were too close! They were born paired and every two letters became one. Here is my sentence with the letters still paired: 䗋⛺峙峊杒➈樇⬲椠刑☢斅刓彞嬦 If you can't see ...
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### Box of text contains hidden message

I invented a novel encryption technique that hides a message in the below text box. ...
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### Help! What's my encoding? ¡××­šwg¿¿uþ}0ã×/Œz0îÏ–þžwóuÜ„

I wanted to share a wonderful message with all of you lovely people on puzzling.SE, but when I typed it in, all that came out was a string of gibberish: ¡××­šwg¿¿uþ}0ã×/Œz0îÏ–þžwóuÜ„ Thankfully I've ...
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### Mission: Impossible 1

Ethan Hunt is alerted by the IMF. They want him to intercept a courier that is working for the super villains Matt Fillimore and Caro Bassanara. Ethan Hunt receives the following cipher from the IMF: ...
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### Mission: Impossible 3

Yesterday Ethan Hunt received the following message: Take Qantas flight number 47, leaving 11 o'clock on the 5th of April. At your destination airport use any bus with number 2, 8, 18 (or bus 18/1)....
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### Recipe for Success

One evening you receive an e-mail from an acquaintance, asking for your help. The e-mail runs as follows: Dear friend, I need your help! I've forgotten the combination to my safe and I need ...
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### Scrambled Songs 2: What is the song this time?

Yeah... this is the sequel to Scrambled Songs which is here. This is to redeem myself from that really easy question: Another scrambled song... 3684-4009-4010-4840-3756-4876-4262-3755-4279 A hint ...
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### Here's another cryptogram! But don't look too far

Here is another cryptogram. Don't look too far. ndfd kx z ygn fh;glbfz Q And also, the 2 is a hint.
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### Break this coded message: SJT LX NY …

SJT LX NY SIVOYFNPAU KZTN HWPQ ZGSKFYQZBZJV OQISAEGEXHO EP LNT TRHIIKK JH PFXYSG KJW HZ TKRP LASXHPTAZ UNMSMAWHCJ OHOGZ FR MOU DH IFCPTL DDIJWQFV PL CLPMQB WTSL WO DSQZ WC GLAVE GWYMQAUQUC JDWMASXQAHH ...
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### There's an ARG I've been working on, and I'm stuck on this puzzle

I've been attempting to solve this ARG named SAN for the past 2 days or so, and I've been stuck on this image for about a day. Are there any algorithms or methods to figure it out? By the way, the ...
271 views

### This and this - 5 cryptograms

Here are some cryptograms for you to solve: ...
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### A picture of Gaspard Monge

In Paris, a famous Nobel prize winner was found murdered in his kitchen. The door of the refrigerator stood wide open, and a small piece of butter had fallen on the floor. On the kitchen table, there ...
305 views

### What was the encryption mapping?

In this Recent Question, what was the encryption mapping? In other words, how did each letter map to its 2-digit counterpart?
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### Find the title and artist of this song

Below, I've used this alphabet: to encode the first eight lines of a song. Find the title and artist. 4c4a’3h4a 3b1d1f3g2a 2e1d 4c3a1b2e 3a2b2b 3g1b3d3e2e 1e3e4a’1e 3b1d1f3g2a 2e1d 3h1f3g 3a4b1d3f ...
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### The Art of Misdirection

You're part of a special intelligence operation trying to predict the location of the next strike for a notorious terrorist group. This group has proven that they are willing to kill innocent people ...
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U PROP BY THERE, USE PARS PAR THERE PROP BY THERE IYBSM PAR YUCR THER, USE YH HS. THINE BP AUQQRS PAUP PAR HGBMBSUN PROP BY GRUTARE UP YHCR YPUMR?
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### Heliocentricity

They approached the man apprehensively. He was aware of their approach, but did not turn to face them. Instead, he kept looking through the window toward the stars. Finally, one of the men gathered ...
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### A Curious Recipe

Little Red Riding Hood received this odd recipe from her grandmother. Hello. Here's a cake recipe you might enjoy! Orange cake: (serves 4) Ingredients: - 111 cups caster sugar - ...
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### Dr. Strangelove or How I Learned to Stop Worrying and Love the Bomb

Can you recover the following two dozens of (well-known) movie titles just from their initials? ...
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### Puzzle of Random Numbers

My friend sent me his puzzle: it's S2LQEQnXk4DP+WsyP1aURD+lz4JSteeOPz3tO7Yiu1dv5fFCr31uegHUpVGqyXk7WjX95TDALus8Gj6nnoGHwj0MLE2AfpB2KTQEIxVvGMyun2XLb+PTcqzVAoFQLr48 ...
288 views

### Looks like ECB — What story is this?

Secrets Revisited A friend sent me the following and wanted to find out if anyone could figure it out. The message was encrypted three times, and all keys and primers were provided. It appears that ...
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### The strength of ciphers against brute force methods - what makes it more difficult but keeps it fair for humans?

EDIT: We have a couple of cipher puzzles on this site which use primitive, simple ciphers like Caesar, Bacon and substitution ciphers, and some of these puzzles combine them. This made me wonder ...
816 views

### Mousehunt cryptogram

I found this puzzle within the game Mousehunt It didn't seem to match any rune system that I know of. Rotating the image also didn't seem to show any useful information, although the first word when ...
437 views

### The Inspector and the Hit man

Inspector Crumblesniff thinks he is on the verge of arresting a notorious Mafia hit man, but he needs your help. First, after a raid on Sal's Pizzeria, he found an address book with these contents: ...
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### I need help on finding out what this means. I know there are 4 steps to it.

The driven ambitious with passionate zeal, Will step forward to discover the author’s reveal, With princes by men, In columns of ten, the experience the answer shall seal. QBOKD KWLSDSYX SC DRO ...
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### The billionaire's necklace

One day, the old billionaire summons his relatives in his study: "I'm very sick and may die soon, but the thought of all of you waiting for my death just to inherit the money makes me even sicker. ...
676 views

### Where am I located?

Note: Not a true story I am currently bored while idly thinking about how I got this job in VA. Sitting at a desk, I think about my work conditions while playing around on Inkscape. Below is the ...
6k views

### Texas Numeric Hidden Message [closed]

This numeric hidden message was found on a seat at Rangers Ballpark in Arlington, TX, with an instruction to "Solve the Riddle". What does it mean?
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### Murder of the President - Part 6

This is Part 6 of the Murder of the President brainteaser/riddle series. If you have not already, check out the answers for Murder of the President - Part 1 posted by Nit Murder of the President - ...
740 views

### The Mysterious Disappearance of Doctor F. Andrews [Part 1]

This is my first real puzzle, so I hope you enjoy it! Sorry if the writing is a little poor, etc.. You are the unstoppable Detective Joshua Brown, and no puzzle can stand in your way! The Case: ...
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### Place names in movie titles - stumped on this puzzle

I'm working on this puzzle where the solution is either a word or phrase with no theme. The first part of the puzzle had incorrect movie titles with cities, states, etc, and the solution to the ...
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### Known Algorithm Attack: Caesar Reloaded

Most of the puzzles here revolve around an unknown algorithm attack. That is, you are given an enciphered piece of text and asked to decode it (and often given a series of hints which describe how the ...
3k views

### What is the cipher behind this circular cyphertext?

I have a cipher and I am wondering if - provided you have both the cipher-text and the clear text, given below, can you describe the cipher which was used? The cipher-text is in this image: I ...
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### Multi-part challenge: riddles and cipher

This is a multi-part challenge; you will need stamina to complete it! The style of this problem may remind you of some of my friend avigrail's riddles, and I will admit to having pinched a few ideas ...
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### A geometric transposition cipher

This is my first cipher puzzle. Here is the ciphertext: ...
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### Descramble the scrambled text

I did something funny. I took a simple phrase. HELLO, WORLD! I generated all rotations of the string. ...