Beijing mahjong rules

Despite being a variant of the national capital, it is rather idiosyncratic just like many regional rules and virtually unknown in the rest of the country. It is unusual to have bias against pung and chow, not that extreme like Japanese "Reach" which has accumulating penalties, though.

Equipments

136 tiles of three suits (characters, circles, bamboos) and honors (four winds and three dragons). The eight flower tiles (four seasons and four flowers) are not used.
Two dice.

Prior agreements

The players agree on what patterns to be recoginsed, how much doubles certain patterns worth, what optional rules to use, and how much a point is worth. A common arrangements include 1, 2, 4 (a point is 1 RMB) and 2, 4, 8 (2 RMB per point).

Seating

It is taken seriously as a very influential element of players' luck and therefore done in a formal fashion. Its details may differ from one group to another.
One of the players, e.g. the youngest, picks four tiles of east, south, west and north, one tile for each direction, places them face down and shuffles them well.
Another player, e.g. the eldest, throws the two dice, counts himself/herself as one, the player to his/her right as two, and so on counter-clockwise, and who is sitting in the seat of the sum of the two dice draws a tile he/she likes, followed by each player counter-clockwise. Alternatively, the shuffled tile are placed face down in a row, flanked by an odd-numbered and an even numbered tile at each end to determine from which end the tiles are taken. Yet another way is to take a tile at will after the shuffling without throwing the dice. Who picks east remains seated, or moves to the seat chosen as east by any appropriate means. The south player moves to the right of the east, west opposite, and north left.

Building walls

All the tiles are turned face down and shuffled well by the four players. Each player builds a wall of 17 tile wide and two tile high with all tiles facing down. The four walls are placed around the center of the table to form a rectangle, or the right ends are pushed forward to make the shape slightly rotated counter-clockwise.

Banker (庄家)

The first banker is the east player. The banker stays when he/she wins or when a hand ends in a draw, and moves to the right side neighbour of the banker when a non-banker wins. A game is four banker rotations.

Breaking a wall

The banker throws two dice and the player in the position of the sum counts the same (the sum) number of stacked pairs from the right end of his/her wall to left and breaks open a gap between the last counted pair and next one. The wall is used clockwise from the gap unlike everything else in the game, that is counter-clockwise. The top tile of the head pair is used before the bottom one, followed by the next pair. Tiles drawn after kong are taken from the tail of the wall.

Deal

Starting from the banker and counter-clockwise, each player takes four tiles at once from the head of the wall in turn, repeated three times to have twelve tiles in hand. The tiles are arranged in a row and placed face down. Then the banker takes first and fifth tile, i.e. top tiles of the first and third pairs from the head of the wall, and each of the remaining three players takes one tile in turn.

Wild tiles (混儿)

After the banker has 14 tiles and the other players 13, the banker takes the first tile from the head of the wall, and places it face up on the wall near its tail for everyone to see. The face up tile is the wild indicator and the four tiles of the same suit and one greater in number are the wild tiles. If it is a nine, one's of the same suit are wild; if it is a wind, next in the order of East-South-West-North are wild, if it is a dragon, next in the order of Red-Green-White. A wild tile can be substituted for any tile in a winning hand. A player cannot make an open set or a kong containing one or more wild tiles. A player cannot discard a wild tile, or he/she forfeits the right to win in that hand.  A player cannot win by claiming a discarded wild tile, either, but he/she can complete a set or a pair of eyes containing a wild tile to win.

After the deal and the selection of wild tiles, the players turn his/her tiles up for him/her to see and no one else.

Play of tiles

Starting from the banker and counter-clockwise, the players repeat the following in turn until one of the players wins or the hand ends in a draw.

• Unless it is the first turn of the banker who already has one extra tile in his/her hand, the current player draws the first tile of the wall from its head.
• If the player cannot win or does not want to do so, he/she discards a tile in front of him/her. Discarded tiles are placed haphazardly in the center of the table so that one has to remember who discarded what.

Winning hand

A winning hand is either

• an eye and four sets, or
• seven pairs.

An eye or a pair is two identical tiles. A set is a run, a pung or a kong. A run is three tiles of a suit in numerical order. A pung is three identical tiles. A kong is four identical tiles melded with a kong call.
A player can substitute wild tiles for any tiles in a winning hand so long as they are not part of open sets or kong.

Chow (吃)

If two tiles in player's hand and a tile just discarded by his/her left side neighbour would be a run when put together, he/she can make an open (or exposed, as opposed to closed or concealed) run from these tiles by saying 'chow', discarding a tile, laying down the two tiles face up to the left of his/her hand together with the claimed tile. A player cannot add or remove tiles to or from open runs. An open run cannot contain fortune tiles. After a chow, turn moves to the right side neighbour of who has done the chow.

Pung (碰)

If a player has two identical tiles in his/her hand and the same tile is just discarded by any other player, he/she can make an open pung by saying 'pung', discarding a tile, laying down the two tiles face up to the left of his/her hand together with the claimed tile. A player cannot remove tiles from open pung. An open pung cannot contain fortune tiles.
If two players say pung and chow simultaneously, the pung wins over the chow. After a pung, turn moves to the right side neighbour of who has done the pung.

Kong (杠)

A kong requires a 'kong' declaration, melding and drawing a supplementary tile. A set of four identical tiles is not a kong without these actions. There are three different ways to do a kong.
a) closed kong. If a player has four identical tiles in his/her hand and it is his/her turn, he/she can make a kong by saying 'kong' and laying down three of the four tiles face down and one of them face up to the left of his/her hand.
b) filling (open) kong. If a player has a tile identical to those of his/her open pung and it is his/her turn, he/she can make a kong by saying 'kong' and adding the tile to the pung.
c) direct (open) kong. If a player has three identical tiles in his/her hand and the same tile is just discarded by any other player, he/she can make a kong by saying 'kong', laying down the three tiles face up together with the discarded tile.
After laying down the tiles, the player who is doing a kong draws a supplementary tile from the tail of the wall and discards a tile. A player cannot add or remove tiles to or from a kong, open or closed. A kong cannot contain fortune tiles. If two players say kong and chow simultaneously, the kong wins over the chow. After a kong, turn moves to the right side neighbour of who has done the kong.

Win (胡牌)

If tiles in a hand of a player and those laid down for chow, pung or kong form a winning hand together with another tile, the player can declare win by saying 'hu' (胡), or whatever all the players can understand as such, and revealing his/her hand. A hand ends when a player wins.

There are three ways to win:

• an own tile (提溜): a tile to complete the hand is drawn from the wall either from its head or tail, which is not brought into his/her hand but placed beside face up on the table;
• claiming a discarded tile (点炮): a tile to complete the hand has just been discarded by other player; or
• robbing a kong (抢杠): a tile to complete the hand is about to be added to an open pung in a (failed) attempt at a kong. The exception is one of three sets of flush, which can be completed by robbing a closed kong as well.

A player can always win by his/her own tile.
A player can win by claiming a discarded tile or robbing a kong only when he/she does not have open sets or more than two wild tiles.
A player can only win by his/her own tile when he/she has four sets or six pairs completed and calls for a pair of eyes with a wild tile.
Some play that a player who has missed a winning tile cannot win by claiming a discarded tile until his/her turn comes or is passed by a pung or a kong.

A player who discards a wild tile forfeits his/her right to win in that hand.
A player cannot win by claiming a discarded wild tile.
A player can win by completing a run or a pung containing a wild tile with a discarded tile or a robbed kong.

A win takes precedence over kong, pung or chow calls.

Draw

A certain number of stacks of tiles remain unused in a hand. It has to be agreed upon before starting. Common arrangements include:

• 7 stacks,
• 7 stacks when number of kong is 0 or 1, 8 stacks otherwise, or
• 14 tiles when there are no kong, increasing by one at each kong.

The wild indicator is not used in any hands but not counted as part of these tiles.
When there are only that amount of tiles remaining in the wall and no one has won, the hand ends in a draw.

Scoring

Each non-winner pays the winner a unit with all applicable doubles applied. The doubles are:

• Banker (庄家): When the banker wins, or when the banker pays.
• Closed (门清): When the winner does not have open sets. He/she still can win by claiming the fourth sets and scores a double for a closed hand.
• Own tile (提溜): When the winner wins by a tile drawn from the wall, either from its head or tail; or when the paying player discarded the winning tile.
• Straight (没混，无混): When the winning hand does not have any wild tiles, or all of them are used at their face value.
• Flush (龙): When the winning hand has three runs 123, 456 and 789 of a suit.
• Seven Pairs (七对): When the winning hand is seven pairs.
• Deluxe (豪华): When two pairs in seven pairs are four identical tiles, none of which are wild tiles, and not a kong. A double is awarded for each of such sets. A wild tile cannot be substituted for one of four tiles in Deluxe.
• Catch Five (捉五魁，捉五): When the winning hand is a gap calling hand with 4C and 6C calling for 5C or seven pairs calling for 5C. A wild tile cannot be substituted for a 5 Character as a winning tile or an eye calling tile in Catch Five.
• Kong Bloom (杠开，杠疵): When a hand is won be a tile drawn from the tail of the wall as part of a kong. Unlike the other doubles, the double for Kong Bloom applies to scores for kongs as well as a winning hand.

Optional doubles are:

• Wild Eye (混悠): when the winning hand has four sets or six pairs completed and calls for a pair of eyes with a wild tile. Some treat this as a sort of Straight hand and scores a double.
• Native Wild Flush (本混龙): when a wild tile whose face value is of the same suit as Flush tiles is substituted for one of the nine tiles of Flush. Some treat this as a sort of Straight hand and scores a double.

Rare events

The points for these events have to be agreed upon before starting a session of the game. They are usually given somewhat high scores, typically 20, but not excessively so because of their purely chance-based nature. They are not doubled for the banker, wall win, or discarding.

• Heavenly Win (天胡): when the banker is dealt a winning hand.
• Earthly Win (地胡): when a non-banker wins by the first discarded tile by the banker.
• Wild Kong (混杠): when a player has four wild tiles.

Kong points

The Winner can score 1 point for each open kong and 2 for closed ones he/she made in the hand. If the winner wins by Kong Bloom, these points are doubled. Many players also double them for the banker.

Irregularities

• False win. If a player declares a win when he/she cannot, he/she pays a) amount he/she falsely claimed to win, or b) predetermined amount usually set to the same as Heavenly Win, Earthly Win or Wild Kong.
• Long/Short hand. If a player has too many or too few tiles in his/her hand, he/she loses the right to win in that hand but has to keep playing.
• Discarding wild tile. A player who does so is treated just like long or short hand.

Variations

Upstairs (上楼): when a hand ends in a draw, next hand is said to be on upstairs, where all the scores are doubled. Some play an hand on upstairs too when the banker is staying three or more hands.

Void suit (断门): some require winning hand to have at least one void suit, i.e. lacking Characters, Dots or Bamboos.

Busted banker (烧庄): if each player discards the same tile without interrupted by any pung, chow or kong at the start of a hand, and the hand does not end in a draw, the banker is busted and he/she has to pay predetermined amount of points (typically 10, or a half of Heavenly/Earthly/Wild Kong) to each of the other players.

At most once: some play that a player can do pung or chow only once in a hand. There are no such restrictions on number of direct open kong even if this rule is in effect.

Additional doubles: especially in online games, all or some of Pure one suit (清一色), All pung (对对胡), Single tile hand (大钓), and Win by last tile (海底捞月) are added as double-awarding patterns. Some score additional doubles for some patterns.

Liability for discarding player (点炮包庄，大包): especially in online games, some play that a player who discarded the winning tile pays on behalf of the other two losers as well as him/herself.