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ID62-The Heavenly Hand, East has Mah Jongg After the Deal
Question: What is a Heavenly Hand?
Answer: If the East player has Mah Jongg after the tiles are dealt out, and before the Charleston, it is referred to as a Heavenly Hand. At that point, the game ends, and the winner (East) is paid double the value of the hand.
Source: Mah Jongg Made Easy 2024, OTHER TIPS AND RULES FOR THE CHARLESTON, bullet #6