YY GAME · 2026-10-28

YY GAME: Explaining an Invalid Group with Rule, Facts and Conclusion

An exercise defines a set as at least three cards of the same rank, with distinct suits.

Editorial note: This is a conditional card-rule teaching example, not a verified description of the named platform.

An exercise defines a set as at least three cards of the same rank, with distinct suits. The submitted group is 9♣ and 9♦. “Invalid group” is a result, but it is not yet an explanation. A YY GAME rules article can make the reason visible in three short steps.

Start with the condition

The required minimum is three cards. State that condition before discussing the submitted group, so the reader knows what is being tested.

Match it to the facts

The group contains two cards. They share a rank and have distinct suits, so those facts do not cause this particular failure. The unmet condition is the minimum count.

Give a bounded conclusion

The group fails the stated set definition because it has too few cards. That finding says nothing about whether the rest of the hand is valid or whether a penalty applies. Those require additional checks and rules. A useful error explanation identifies the failed condition without inventing other faults, punishments or a platform-specific error code.