The Secret to Social Deduction Is Contingent Information

Social deduction games deliver a puzzle experience unlike any other. They ask players to consider both the information they receive and its source. The best ones create puzzles from interlocking facts that don't make sense in isolation, requiring players to judge how much to trust each clue. This type of challenge is driven by what I call “contingent information”, which provides three benefits:

1. It creates goals for players.
2. It encourages discussion.
3. It ties deductions to social trust.

Contingent information is any fact given to a player that becomes more useful only when combined with other facts. For example, the Chef in Blood on the Clocktower knows how many pairs of evil players sit next to each other, but this alone is not very helpful. But if the Chef then learns where one evil player sits, they can narrow down the others' locations. By contrast, in Mafia, the Cop simply learns whether a player is Mafia, a fact that does not require additional knowledge to use.

Contingent information naturally creates goals because players want to make sense of what they have. In my social deduction game, Legends of the Boatman, each player starts with three factual statements: two true and one false. This gives players an immediate goal: test their statements to find the lie. The reward for discovering which statement is false is the certainty of knowing they can trust their other facts.

The need for additional information to make sense of what you have encourages conversation with other players who might know what you need to solve your puzzle. In Blood on the Clocktower, many roles start with contingent information pointing them toward specific players. For example, the Librarian knows one of two players is a particular Outsider, a role with powers harmful to the good team. This gives the Librarian an immediate reason to talk to those players and see what they claim. Since social deductions rely on conversation for their fun, good conversation starters are essential.

Contingent information creates the kind of puzzle that makes social deduction unique, where facts about the game become entangled with their sources. Players enjoy figuring things out, but the puzzle is too easy if all information is reliable. If your information depends on another player's clues to make sense, you must also consider how much you trust them. This creates opportunities for evil players to derail deductions with a well-placed lie, which is the type of thing players remember from playing as the evil team, just as brilliant deductions form memories when playing as the good team.

If you want to create a social deduction game that balances deduction with social engagement and creates entertaining discussions, contingent information is the solution you want. Distribute incomplete facts among players so they must rely on each other to understand the game.