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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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2answers
192 views

Just a Simple Number Crossword

I made a small number crossword for my mathletes club that I thought I'd share. It's not too hard, I think it's just right for a coffee break. Have fun! (Edit: No answer has a leading zero)
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5answers
586 views

History Calls - Twice!

You'd send a letter to me, but I'm not quite what you think. You'd send a letter in me, but only if you didn't know me. I was a gem in my day for being both bold and precise. I stood ...
17
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1answer
496 views

A letter with no particular backstory

So, I was walking down the street when this paper materialized just in front of me, as if from thin air. I'm not sure if I can decipher it, maybe you can? It also smelled like fish a bit.
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1answer
168 views

A fun series of riddles!

All of the clues will lead up to the key for a Vigenere Cypher: eutnn wo vvsf. Clue 1 (from www.riddles.com) I'm by nature solitary, scarred by spear and wounded by sword, weary of battle. I ...
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1answer
117 views

Riddles and ciphers / All good ways to flex the mind / Can you solve my task?

I have arrived new / Here with ciphers for your eyes. / Can you solve this task? ...
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2answers
95 views

Cyrus' Adventure (Part 7)

The wall opened. Cyrus and T.E.D. got out of the room. Suddenly, the passageway started collapsing! Cyrus was terrified. T.E.D. grabbed Cyrus and quickly rolled out of the passageway. They got into ...
43
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11answers
6k views

Geography at the pixel level

(enlarged version) The answer is a group of islands.
2
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0answers
197 views

Can you solve this? Cipher I found

Here is the cipher you need to solve, it is an actual English text: ...
5
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2answers
186 views

Find the result of this dual key cipher

I came up with a neat little cipher that I'm calling the dual key cipher. The basic premise is that there are two cipher keys that, when used together can decode the cipher text against a given ...
10
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1answer
468 views

Find My Mission For Me

I am a spy for the CIA. Since I am in a hostile territory, my next mission was given to me in a very coded manner. Today, while playing chess in the local park a briefcase landed on my head. Feeling ...
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6answers
252 views

What words Atbash plus Caesar cipher to other words? [closed]

If you Atbash cipher plus Caesar cipher after, you get a new set of ciphers, and I tried 4-letter words for Atbash plus Caesar shift 1 and I got: cams <-> yaoi ghat <-> Utah haji <-> tars ...
9
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3answers
312 views

An Aklahp Mystery

You are a detective in the city of Aklahp, which has had some problems with crime in the past. It used to be just simple burglary or breaking an entering, but things have been getting worse recently. ...
9
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4answers
3k views

Detention in 1997

As summer break is coming up, you have started to misbehave in school, getting sent to detention quite often. On June 20th, something interesting happened, and made detention a little more fun. You ...
8
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1answer
519 views

How to decipher

I received the following challenge as a homework problem. Not much info is provided with it, except for the word Decrypt! at the end. This problem is online on a password protected school site. So I ...
6
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2answers
141 views

Cyrus' Adventure (Part 6)

The robot's program started running. It twisted its head, torso, arms and legs. After a few minutes, it stopped twisting and vocalized a few sentences, "Hello master. I am T.E.D. and I am here to ...
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1answer
144 views

Unknown Cipher? [closed]

gX18gICAgIF9fXyAgX18gICAgICBfXyAgIF9fICAgX18gICAgICAgICAgICAgICAgICAgICBfX18gICBfXyAgIF9fICANCi8gX2AgLyAgXCAgICAgfCAgLyAgXCAgICB8ICBcIC8gIFwgfF9fKSAgL1wgICB8XC98IHwgfFwgfCB8X18gICB8X18pIC8gX2AgDQpcX18+...
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1answer
262 views

Coordinated efforts

I was showing off my knowledge of obscure geography trivia to my father. He admitted he'd never remember all those details, but insisted that there was a certain other topic where nobody could ever ...
25
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1answer
571 views

Invade the Pyramid if you Dare

Before you lies a pyramid, with a giant statue blocking the entrance. ...
5
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1answer
265 views

A strange message full of dice came in my mail

So I got a package today that contained the strangest contents. It was a set of dice, each of them numbered in one of the corners. Arranged, this is what numbers or characters displayed on each dice, ...
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1answer
115 views

How to decrypt simple binary code to alphabet

Part of an alphabet is given by the code: This code is used by Fred to send a message home to his mum. She receives the following signal which includes a parity check digit on each word. ...
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1answer
206 views

Part of a challenge, from a group of adults, who break ciphers

I am part of a group of adults, a cipher club who like to decode random ciphers, from texts to symbols and other things. We were presented with a set of 5 ciphered text, and we have managed to crack 3 ...
3
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1answer
362 views

What in this world is she trying to say?

I happened to meet one of my friends after about a couple of years. Obviously we both were very happy, but still, she didn't leave her habit of challenging me to decipher what she was saying. I ...
9
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1answer
388 views

Where are they being held?

In my dream, some People asked me for help. They said I should wake up. So I woke up and there was this letter. Dear Percy We got caught and only you can help us. You've 60 minutes (try it ...
7
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1answer
576 views

The garden where everything is possible

An old man spoke to me today. He said: "A long time ago, I buried something very important. That was 20 years ago." After he said that, he gave me a note where it was written "Hyih Jbimjbilom ...
15
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3answers
479 views

The programmer who loves dogs and puzzles

Your programmer friend, Daniel, went on a two week long vacation, and asked you to look after his adorable dog. He loves dogs, and he certainly doesn’t want a stranger to do this job, so you agree. ...
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0answers
141 views

Eight Sisters Treasure Hunt

Eight sisters don't guard the essential hoof This is from the game CreasureQuest, so I suspect the solution in context with the historical background (the lost treasure of the Flor de la Mar, Afonso ...
12
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1answer
431 views

Jealous, Lying, or unAmerican

I opened my email today to find this odd image. I suddenly had a strange craving, which fortunately I was able to satisfy outside my local Starbucks—-I happened to be driving by literally as the ...
11
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2answers
339 views

I'm drawing a blank on my name, help me out?

I'm a wrestler, I know that because I just got hit over the head harder than I've ever been hit before. So hard, in fact, that while I'm trying to remember my name... all that comes up in my head is: ...
9
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1answer
1k views

Someone scrambled my calling sign- who am I?

Before I left the scene of the crime I left my calling sign... But on the news the next morning all that was left was the following: .Iaaabmmnt Which seems to ...
9
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2answers
768 views

How will you save Mike?

A direct hint: this question. Question starts from here: You are Dr. Nathaniel - a renowned archaeologist, and involved in a research about an ancient site. But, there is only one problem - the ...
33
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2answers
3k views

Can anyone tell me why this program fails?

...
17
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1answer
580 views

Silly Sally's Movie

My friend Sally and I love watching movies on Friday nights. This week it's her turn to pick a movie. Sally: "I won't tell you the name of the movie but I will say this: I love eating peanut ...
12
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5answers
496 views

Unlocking the dungeon door

Any feedback is welcome. I'm new to puzzling in general so please let me know how long it took you to come up with your answer and what your thoughts were. I have tough skin. Hint Hint 2
4
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1answer
240 views

Bro's password… must've forgotten

My overseas friend has forgotten the password to his SackExpunge account, and the only information he wrote down about it was this: Username: LiveSound Password: ...
0
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0answers
89 views

Help deciphering number cipher

21,14,01:15,03,01:19,11,10,10:02,15,18,01:21,15:05,01,13,03,11,21,01:21,14,15,21,01:19,14,15,21:21,15,19,21:19,01,05,01:09,05,15,08,01,03:09,03:04,01,07,21,14,21:21,21,11,03,20 9,10,13,1 we ...
11
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2answers
481 views

Oh boi! Dis waas never Engliz! #2

This puzzle is second in the series, the first one being this. But these are related in no way. Below are some weird combinations of letters, which are actually words translated in some different ...
7
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1answer
403 views

Oh boi! Dis aint Engliz! #1

First some Engliz: These weird combination of letters are actually words translated in some different languages, and concatenated. Each line has one word translated in different languages. These ...
25
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1answer
2k views

Real life puzzle: Unknown alphabet or shorthand

User JellicleCat posted this on linguistics stackexhange a few years ago. None of us were able to come up with a satisfying answer but most seemed to agree that it was an idiosyncratic cipher or ...
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3answers
2k views

A Wacky, Wacky Chessboard (That Makes No Sense)

So yesterday I found this in the mail. A chessboard. But on the squares, things were written. Plaintext version: ...
3
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1answer
124 views

Cyrus' Adventure (Part 4)

Cyrus opened the box carefully. Inside there was a strange totem made of metal. Cyrus decided to keep it. Suddenly, a cupboard opened by itself, and showed a secret passageway. Cyrus grabbed other ...
14
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0answers
604 views

Never Completed Game - Difficult Riddle

The seventeenth of the primes. Its twin is twentynine. Po. Let’s drive. Bye, Alfonsín. Add seven triangular. Sweet. It named the Valley. This riddle is taken from https://www.nevercompletedgame....
9
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0answers
742 views

Crack the pigeon code

Can you crack this message? It was discovered in a chimney in 2012 attached to a carrier pigeon and was most likely sent during the D-day invasions. The GCHQ was not able to crack it, even after ...
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1answer
193 views

UNKNOWN CIPHER - NEED HELP DETERMINING (SOLVING)

I am trying to figure out how to decrypt and also re-encrypt potentially the following, meaning that i could write a random text string and it would generate that encryption and also decrypting it ...
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1answer
84 views

Qz heona “cvpxyr evpx” - how can I solve this?

Here is the puzzle: Qz heona “cvpxyr evpx”. Please, can you help me solve it as I am struggling! Thank you!
18
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3answers
681 views

What force is more potent than love?

A few quotes about Love.... What force is more potent than love? True love is selfless. It is prepared to sacrifice. We are all born for love. It is the principle of existence, and its ...
0
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1answer
170 views

Solve this cipher puzzle [closed]

PJb6bN5lUW3R0ZbRrfWMf4swe6CZyqBPS4GT8+bzoLE= This is a cipher that cannot figure out. It's probably a url but it doesn't look like one. I'm thinking its a math ...
7
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3answers
320 views

The Secret Meeting

In a special operation our unit was able to intercept encrypted chat messages from a group of spies who plan a secret meeting: Ifmmp fwfszpof! Jk Krzgb Wyt? Fwj dtz htrnsl yt ymj Sjb Djfw'x ...
10
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1answer
185 views

What Library? [first puzzle]

ywfwkak 33:21 ...
5
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1answer
184 views

At Two-Twenty-One, B, Baker Street

Inspector Jane Watson, of New Scotland Yard, paid a call on her good friends Dr. Shirley Holmes, and her roomie, the famous consulting detective Georgia Lestrade. Ms. Holmes answered the door. "Good ...
6
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2answers
244 views

A strange day at the beach

You are enjoying a nice day the beach when suddenly you see a note and phone floating in a bottle marqued “FREE” and you wonder how they shoved the Iphone X+ in there. Then you realize that there is a ...