Mahjong rules in Yangzhou, Jiangsu -- another regional mahjong with large number of patterns

Yangzhou is where Yangzhou Fried Rice originated, it's also known as birthplace of historical beauties.

Equipments

136 tiles of three suits (characters, circles, bamboos), honors (four winds and three dragons).
Two dice.

Banker rotation and winds

Banker stays if he/she wins and it moves to his/her right side neighbour if a non-banker wins or in case of a draw. Some play that the banker stays if a hand ends in a draw.

Each player is assigned a seat wind: the banker east, his/her right side neighbour south, the player sitting across the table west and his/her left side neighbour north.
A round wind starts with east and changes to south, followed by west and lastly north when banker moves to the first banker of the game.

A session of a game is four banker rotation. Some play eight rotations.

Breaking wall

Use sum of two dice thrown by the banker to determine whose wall to break and the smallest die rather than the sum to number of stacks to leave. The banker grabs 14 tiles before starting a hand and the other players 13.

Play of tiles

• Can chow as well as pung and kong.
• If no one wins when there are no tiles left in the wall, the hand ends in a draw, or there's no dead wall.
• More than one player can win on a same discarded tile.
• A player has to wait until his/her own turn to win if he/she missed a winning tile.
• A hand must be at certain score or higher to be eligible for winning. It is set to 7, 10, 13 or 18 points, or the points of Twin Runs or 3 points more than that.

Payout scheme

• In case of win by own tile, each of three losers pay the winner the score of the winning hand,
• In case of win by discarded tile, one who discarded the winning tile pays the winner twice the score of the winning hand and the other two losers nothing.

Score of a winning hand is sum of points of all applicable patterns. Points for non-minor patterns tend to become higher in newer rules, along with minimum requirement.

• Old(?): Twin Runs = Minimum = 7, Mixed One Suit = 10
• Common: Twin Runs = 10, Minimum = 10 or 13, Mixed One Suit = 15
• New: Twin Runs = 15, Minimum = 18, Mixed One Suit = 20

1) Minor patterns

• Fully Closed (门清): 1. no open sets before winning.
• Common Win (平胡): 1. four runs. the eyes are not honors.
• Win by Own Tile (自摸): 1.
• Single Call (丫子，独吊): 1. can win with only one tile, like 1 and 3 calling 2, 1 and 2 calling 3, or eye calling hand.
• Void Suit (缺一): 1. a winning hand without one suit and honors.
• End Eyes (幺头): 1. the eyes are 1 or 9.
• No Terminals (断幺): 1. a winning hand without 1s, 9s and honors.
• Side-by-side (齐相): 1. two runs in two suits with the same numbers. e.g. 345C 345D
• Tandem (连副): 1. two runs in tandem in a suit, e.g. 345B 678B.
• High-low (老少): 1. 123 and 789 in a suit.
• Closed Pung (子格、招): 1.
• Open Kong (明杠): 1.
• Closed Kong (暗杠): 2.
• (pung of) Seat Wind (门风): 1.
• (pung of) Round Wind (圈风): 1.
• (pung of) Dragon (中,发,白): 1.

2) 2/3-3/4 of Mixed = 7/10/15

• Twin Runs (一板). two identical runs. e.g. 678B 678B

3) Mixed = 10/15/20

• Mixed One Suit (混一色)
• All Pung (对对胡)
• Three Runs Side-by-side (三副同). e.g. 345D 345C 345B
• Two Tandems Side-by-side (双连双喜，双飘). e.g. 123B 456B 123C 456C
• Two High-low Side-by-side (双飘). e.g. 123B 789B 123C 789C
• Straight Flush (一条龙). 1 through 9 of a suit forming three runs.

4) 2--2.5 times Mixed = 20/30/50

• Four Runs Side-by-side (四副同). e.g. 345D 345B 345C 345D
• Double Twin Runs (双板板). e.g. 456C 456C 234D 234D

5) Pure = four times Mixed = 40/60/80

• Pure One Suit (清一色)
• Triplet Runs (铁板). three identical runs. e.g. 234D 234D 234D
• Double Twins Side-by-side (双板双喜). e.g. 456C 456C 456B 456B
• Double Twins High-low (双板双老). e.g. 123D 123D 789D 789D
• Double Twins in Tandem (双板双连). e.g. 345B 345B 678B 678B

6) Multiples of Pure

• All Honors (风清): pure x 4 (or pure x 2)
• Quadruplet Runs (钢板): pure x 8 (or pure x 2). four identical runs. e.g. 123C 123C 123C 123C

7) Combination patterns with bonus points

Only applicable to the 18 point minimum (15 point twins, 20 point mixed) rules.

• Straight Flush with Twins (板龙): 50. e.g. 123C 456C 789C 456C
• Mixed One Suit with All Pung (混对对): 50.
• Mixed One Suit with Straight Flush (混龙): 50.
• Mixed One Suit with Straight Flush and Twins (混板龙): 80.
• Pure One Suit with All Pung (清对对): 130.
• Pure One Suit with Straight Flush (清龙): 130.
• Pure One Suit with Straight Flush and Twins (清板龙): 160.

Exceptions to the payout scheme

A "liable" player has to pay for him/herself as well as the other two losers.

• Who gives the third open set that is a chow to a player winning with pure one suit has to pay for the other losers as well as him/herself.
• If a player chows tiles of the same suit three times, he/she must aim for pure one suit.