Rules

Cicada 3301

SIH-kay-duh thirty-three-oh-one
The anonymous internet puzzle series of 2012 to 2014: cryptographic challenges spanning Tor, runes, GPS coordinates, and a partly unsolved runic book, the Liber Primus.
Documented

Three Januaries

On January 4, 2012, an image on 4chan announced: we are looking for highly intelligent individuals, look for the hidden message. Solvers chased steganography, book ciphers, prime numbers, Mayan numerals, and physical posters in fourteen cities worldwide. Puzzles repeated in 2013 and 2014, culminating in the Liber Primus, a book in runic script, partially decrypted into warnings: do not trust the path you find, question everything. Those who finished reportedly received private invitations and instructions of silence. A PGP-signed 2016 message warned of impostors; the last authenticated communication dates to 2017. The Liber Primus remains largely unsolved.

Assessment: Documented by the solver community's complete archive. The silence protocol is why there is no finish-line photo.
Stories

The candidate list

Theories: intelligence recruitment, NSA or GCHQ, the technical sophistication and global logistics suggested institutional backing; a security firm headhunt; a cyberpunk art collective; or the first ARG with no product. The warning pages read less like spy tradecraft and more like doctrine, anonymize, mistrust institutions, build privacy tools, which points to cypherpunk true believers rather than an agency. No one has ever credibly claimed authorship, and no winner has ever credibly described what happened next.

Assessment: Every theory is documented as a theory. The zero-claimant record after a decade is itself the strangest datum.
Interesting claims

The puzzle was the hiring freeze

The claim: Cicada's genius is that the puzzle, not any project behind it, was the whole point, a filter that found, organized, and then dissolved a global cryptography community, and the unsolved Liber Primus functions as a permanent honeypot: anyone smart enough to matter is still working on it, for free, forever. Verdict: unfalsifiable but elegant, and the archive notes it is the only recruitment operation whose product might be the recruitment. The cicada emerges, sings, and vanishes underground. It was never hiding. It was molting.

Assessment: undefined
Sources and further reading
  1. The Cicada 3301 solver community archive (5,157 files)
  2. PGP-signed communications, 2012-2017
  3. Liber Primus partial decryptions
  4. 4chan original post, January 4, 2012
Worth asking

If the winners were told to stay silent, did the puzzle ever end?

Open in the interactive archive
GR8YFILES · competing origin stories, labeled by the strength of their evidence · readers 14+