In a play-by-post game that requires a player to commit to a secret decision and later reveal that decision publicly, how can a player certify that they did so honestly without relying on good faith?
Consider the following game scenario.
- Alice commits to a decision, like pre-programming an action she will take. An onlooker might notice she's doing something but they wouldn't know the particulars.
- Though Bob doesn't know exactly what Alice is up to, he commits to a decision in response to that, like reacting to stop her. Resolving his decision will depend on resolving her decision.
- Alice has to reveal what her committed decision was after the fact in order to resolve it at this point along with Bob's reaction to it. If she's being honest or has a way to certify what her decision was, this is fine. If she is able to lie, she could change her decision retroactively.
Are there common tools, techniques, or conventions to support this? At a table, Alice could simply write her decision in a folded note card and reveal it later; or in a board game, she could play her action card face down and reveal it later. These common table conventions don't translate well to online play. So, how can Alice certify her secret decision to be revealed on a delay?
Assume the following about the game, its rules, and the players:
The system is not freeform. It has rules that match the scenario given above.
Even if the players know and trust each other, they still need (or want) a way to certify their decisions without relying on good faith.
The gamemaster might also be a player (possibly even an adversarial one) and is not exempt from the need (or want) of a way to certify their decisions without relying on good faith.