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ID58-Process After a Player Declares Mah Jongg
Question: What happens once a player declares Mah Jongg?
Answer: Once a player declares Mah Jongg, all players must wait to verify the player’s Mah Jongg is valid before tossing in their hand. This will avoid another player’s hand from being declared dead. Finally, congratulate the winner!
Source: Mah Jongg Made Easy 2020 page 16, #1