A short timeline
- January 4, 2012: the first image appears on 4chan, inviting readers to find a hidden message. The hunt runs for nearly a month.
- January 4, 2013: a second round begins. Marcus Wanner solved its first puzzle. Those who answered questions about information freedom, privacy and anti-censorship were invited to a private forum and given a project.
- January 4, 2014: a third round is posted on Twitter. It remains unsolved.
- January 2016: a further message appears on Twitter.
- April 2017: the last verified message, signed with OpenPGP, says unsigned puzzles are not genuine.
What made the puzzles famous
Cicada crossed between the online and real worlds. Clues included digital images with information hidden inside them, a telephone message, websites and paper signs with QR codes posted in physical locations. Solvers had to recognize references to literature, poetry, art and music as well as handle cryptography. That mix meant no single person was likely to have every skill, so strangers teamed up online to share their findings.
The kinds of skills involved
You do not need to be a security expert to understand the basics:
- Steganography means hiding a message so nobody knows it is there, for example inside an image file.
- Ciphers scramble a message that is in plain sight. The classic ones are a good place to start: try the Caesar cipher and the Vigenère cipher.
- Encodings such as binary are not secret, but puzzle makers use them as layers.
- Digital signatures prove who wrote something. Cicada's OpenPGP signature is why people could trust a clue.
Why it still fascinates people
Cicada has everything a good mystery needs: an unknown author, a real test of skill and an ending nobody has reached. If you come across a strange code in a game or online puzzle hunt, paste it into the cipher identifier.
Try your own hunt
Want a taste of the same feeling? Escape the Cove chains eight real ciphers together, ending in a lock whose keyword is hidden earlier in the game. For a daily challenge, try Cipher of the Day, or see all our games.
Sources: Wikipedia, Cicada 3301.