Related Clues:

• Board game regulation
• Are awesome
• Principle that provides guidance to appropriate behaviour
• Act like a monarch?
• "Don't count your chickens before they hatch," for one
• 'No shoes in the house,' for example
• 'Roll doubles to get out of jail' or 'You do not talk about Fight Club'
• “Starting with the Banker, each player in turn throws the dice,” e.g
• Regret carrying large measuring stick
• 'No running,' e.g
• What a king does
• "Only X's and O's" in tic-tac-toe, for one
• 3 strikes and you're out is one
• Adage, dictum
• A do or a don't