| Name of Game | Systems |
| Type | thinking |
| Age Range | 7-adult |
| Number of Players | 2-30 |
| Playing Environments | anywhere quiet |
| Shared Equipment | none |
| Individual Equipment | none |
| Summary | One team secretly devises a system that they will use to answer any question asked of them by the other team. The other team tries to figure out their system, with a maximum of three guesses.
For example, Team A decides that each answer they give will start with the first letter of the first name of the asker. If Sam asks Amy, "How old are you?" Amy might answer, "Seventy-nine." Answers need not be truthful. The system can be alphabetical, as in the previous example, numerical, thematic (such as always making some reference to nature), or even physical (such as always rubbing one's hands together while answering). Any system is legitimate as long as it is reasonably possible for the askers to figure it out. Using the middle initial of the answerer would be an example of an unfair system, because the askers are unlikely to know what that initial is. A completely random system is also not allowed. Players on the asking team take turns asking questions, and they may guess at any time. |
| Rules | A time limit can be set, or each round can continue until the askers succeed or give up. Answerers may help each other if one can't think of an appropriate answer, and they are obligated to correct any answers given that do not fit the system. |
| Comments | The answering team should keep systems fairly simple at first. Even the simplest system is often surprisingly hard to decipher.
The asking team should try to distribute questions evenly among the answerers. This game is often very funny, revealing a lot of cleverness in the answerers. |