Coup: Inquisition is a small, yet cunning, promotional expansion released in Brazil that introduces an interesting dynamic to the classic Coup. It's not a standalone game, but rather an addition that subtly alters how players interact with the Duke's influence, one of the most powerful characters in the base game. The central piece of this expansion is a double-sided coaster: one side shows two Dukes, maintaining the original rules, and the other side displays the Inquisitor, which is where the magic happens.

When the coaster is on the Inquisitor side, the action of collecting three coins with the Duke becomes a bit riskier. If a player declares they have the Duke to take their three coins, any other player can immediately claim to have the Inquisitor's influence. If this claim is successful, the Inquisitor player steals one of the three coins from the Duke, leaving them with only two. Of course, the claim of being the Inquisitor can be challenged, adding another layer of bluffing and deduction. If multiple players try to be the Inquisitor, preference is given to whoever has less money; in case of a tie, the Duke decides who gets the coin. Additionally, the expansion introduces a new action, 'Subvert', which allows a player to pay one coin to flip the coaster, alternating between the normal rules and the Inquisitor rules. This small change can have a significant impact on bluffing strategies and coin management, making Coup matches even more tense and unpredictable.