Prose & Codes

Prose & Codes is a cryptogram puzzle game that uses literature as its source material. Every puzzle is an excerpt from a public-domain literary classic — Project Gutenberg holdings — encrypted with a substitution cipher, and your job is to decode it. Over 400 hand-selected passages span eight genres, from children's stories to horror, from canonical canon to forgotten gems.

The pitch underneath the puzzles is that decoded passages might point you to books you'd actually want to read. Each puzzle credits the source, and every text is free to read or download in full from Project Gutenberg's online library — one click from the in-game interface. Ten percent of every Steam sale goes back to Gutenberg to support the volunteer effort that digitized everything in the game.

Four difficulty settings adjust how much of the cipher key is pre-filled. Dark mode and optional enlarged cipher text reduce eye strain over long sessions. The piano soundtrack stays in the background. The Mortimer Adler quote on the store page — about how many books can get through to you, not how many you can get through — is the explicit ethos of the project.