Two teams compete to deliver coded messages without letting their opponents work out their meanings. The standard game is for 4–8 players, with 2–4 players per team.
Each team receives four numbered words (1–4), shown only to that team. The words remain fixed throughout the match. Players take turns as their team's Encryptor.
Both Encryptors receive a private three-digit code using three different numbers from 1–4. They compose three distinct clues, one corresponding to each digit's secret keyword. For example, if your keywords include 1: FOREST, 2: SHARK, 3: MOON and 4: CASTLE, a code of 3–1–4 might produce the public clues Orbit / Pine / Fortress.
Clues may be words or phrases and must refer to the keyword's meaning. No keywords or translations as clues; no spelling, pronunciation, length, position, or private references. The clue must be understandable from public knowledge. Never reuse a clue in a match. The Encryptor may not help their team interpret the clues.
The White team presents first, followed by Black. Teammates must guess their own Encryptor's three-digit code. Starting in round two, the opposing team also attempts an interception by guessing that same code. Each team may submit one sealed answer per transmission. The opposition's guess is resolved before the home team's guess.
In round one there are no interception attempts—use the clues to begin your deductions. In later rounds, examine your notebook: every revealed clue is filed beside its actual keyword number, helping you identify patterns in the opposing team's secret words.
A successful interception earns your team 1 Interception token. If your own team misreads its Encryptor's code, you receive 1 Miscommunication token. Reach 2 Interceptions to win or suffer 2 Miscommunications to lose. Both transmissions always finish before checking victory.
The match lasts at most eight rounds. If winning and losing conditions collide, or no team wins after round eight, compare each team's score: Interceptions minus Miscommunications. If still tied, each team guesses all four opposing keywords. The team with more correct guesses wins, or they share victory on another tie.
Players join alternately onto White and Black teams (seat numbers 1, 3, 5, 7 are White). Current Encryptors rotate among teammates each round. The shared top bar shows room controls and lets you return to the lobby. Spectators can see only public clues and results. Solo test controls all seats and cannot preserve hidden information from the human tester.
Decrypto was designed by Thomas Dagenais-Lespérance and published by Le Scorpion Masqué. This implementation uses an original keyword collection.