2015年12月26日土曜日

Wuhan mahjong rules

The variant's name is Red-wild-kong (红中赖子杠), in reference to bonus given to kong of single tile Red dragon and wild card. It features a wild but fair doubling system in that a player attempting to score more points with doubles also has to pay more with these.

(26 March 2016)Revised with many minor corrections and additions.
(2 April 2016)Added the "peel" kong variation.
(3 October 2018)Added a three-player version.
(10 December 2018)Corrected the description of the peel kong variant. Added more examples of minimum point requirements. Added description of real world scoring where points are divided by 10 or 20 and rounded.

Reference


Equipments

136 tiles of three suits of Characters, Bamboos and Circles, and Honors of four Winds and three Dragons.
Two dice.

Seating

Seats are chosen by a lot before every session of the game. There are two methods, traditional and contemporary.
The traditional way. Pick four wind tiles, one for each direction, place them face down on the table and shuffle well. Each player takes one. Who draws East throws two dice and sum of the pips  determines East seat. Rolls of dice are counted from who throws the dice as one, his/her right side neighbor 2, and so on counter-clockwise.
The modern way is used on automatic dealing tables. Each player picks a tile from his/her own wall. Who picks the largest number becomes East, second largest South, third West and the smallest North. Suits are compared in case of a tie. A Circle beats a Bamboo, which beats a Character. The Honors rank lower than the suits, and among themselves, from the highest to lowest, East, South, West, North, Red, Green and White. When more than one players draw identical tiles, each of them draws a tile to break a tie. Who becomes the East throws the dice to determine the East seat.

The east player moves to the east seat, the south to the right of the east, the west opposite, and the 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 wall are placed around the center of table to form a rectangle, or the right ends are pushed forward to make the shape slightly rotated counter-clockwise.

Banker rotation and session of the game

The East player is the first banker. The banker stays when he/she wins or in case of a draw. It moves to right side neighbor of the current banker when a non-banker wins.
A session of the game is four banker rotations. When three complete sessions are played, win and losses are usually around 500 points  800 to 1200 when exceptionally (un)lucky, and around 200 in uneventful cases.

Breaking wall

The banker throws two dice and the player in the position of the sum counts stacked pairs from the right end of his/her wall, the end as 1 and clockwise, until the smallest pips of the two dice, and breaks open a gap between the last counted pair and the 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.

After the banker grabs fourteen tiles and the others thirteen, the players turn his/her tiles up for him/her to see and no one else.

Wild tiles (赖子)

The first tile of the wall after the deal is turned face up and placed on the dead wall, that is the last ten tiles not used in the hand. This is the wild tile indicator. Wild tiles are tiles one greater than the indicator; if it is a Nine, they are Ones of the same suit; if it is an Honor, next ones in the order of East-South-West-North-Red-Green-White-East. If the indicator is a North, Green Dragons, instead of Red, are wild because Red Dragons will never be wild.
A player can substitute a wild tile for anything but a Red Dragon in a winning hand. He/she can also do a single tile kong of a wild tile. He/she can discard it as well. A discarded wild tile does not go into the discard pool but player's own chow/pung/kong area.

Red dragons

Red dragons are different from the other tiles in that they cannot form a pair or a set. A player can only do single tile kong of a Red dragon or discard it. He/she can also keep them in hand if he/she does not intend to win in that hand. A discarded Red dragon does not go into the discard pool but player's own chow/pung/kong area. He/she cannot make a pung or a four-tile kong out of them. A player cannot win if he/she has Red dragons in his/her hand.

Winning hand

A regular winning hand must have
  • a pair of eyes, that are two identical tiles of 2, 5 or 8 unless it is all pung or pure one suit where one can use a pair of any identical tiles as eyes; a pair of wild tiles do not meet the condition unless their face value is 2, 5 or 8, while it is OK to wait for any 2, 5 or 8 with a wild tile to complete a pair;
  • an open set, that is a set of three tiles made by a chow or pung (or direct kong) call;
  • three sets that can be open, closed or any mixture of these; and
  • all red dragons discarded or laid down as kong.
A set is either a run or a pung. A run is three tiles of a suit in numerical order, for example, 2 Bams, 3 Bams and 4 Bams. A pung is three identical tiles. A set of four tiles made with a kong call is regarded as a pung of three tiles and a kong at the same time.
All honors and all eyes are the only exceptions to the rules above, in that they require an open set and lack of red dragons but the rest do not have to form an pair and sets.

Play of tiles

Starting from the banker and counter-clockwise, each player repeat the following steps in turn until one of them wins or the current hand ends in a draw:
  • (draw) takes a tile from the top of the wall unless it is the first turn of the banker when he/she already has one extra tile in his/her hand; and
  • (discard) discards one unnecessary tile from his/her hand into the discard pool in the center of the table if he/she does not win or does not want to do so. Discarded tiles are placed rather haphazardly so that players have to remember who discarded what.

Chow

If two tiles in player's hand and a tile just discarded by his/her left side neighbor 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 in the corner to his/her left, and putting the claimed tile together with them. An open run cannot contain wild tiles. A player cannot add or remove tiles to or from open runs. After a chow, turn moves to the right side neighbor of who has done the chow.

Pung

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 in the corner to his/her left, and putting the claimed tile together with them. An open pung cannot contain wild tiles. A player cannot remove tiles from open pung. If two players say pung and chow simultaneously, the pung wins over the chow. After a pung, turn moves to the right side neighbor of who has done the pung.

Kong

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 four 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, during he/she has one extra tile, he/she can make a kong by saying 'kong' and laying down the four tiles face down in the corner to his/her left.
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 and adding the discarded tile to them just like an open pung.
d) single tile kong. If a player has a red dragon or a wild tile and it is his/her turn, during he/she has one extra tile, he/she can make a kong of that tile by laying it face up in the corner to his/her left.
The player, then, after performing one of these actions, draws a tile from the tail of the wall to bring the number of tiles in his/her hand back to normal, and discards an unnecessary tile. A four tile kong cannot contain wild tiles. A player cannot add or remove tiles to or from kong. If two players say kong and chow simultaneously, the kong wins over the chow. After a kong, turn moves to the right side neighbor of who has done the kong.

Winning

If tiles in a hand of a player and those laid down for chow or pung 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:
  • own tile (自摸): 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 discard tile (放冲,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.

A player cannot claim a discarded wild tile, but he/she can claim a non-wild tile to complete a set or a pair containing a wild tile when winning.
A minor win (explained later in the scoring section) is only possible when a player has one or no wild tiles. A wild tile counts even if it is substituted for its face value.
There is usually a minimum point requirement for a valid win, for example 8 points (three doubles) to keep difference between minimal and maximal wins within a comfortable range. A player can only win when he/she can receive more than or equal to the minimum point from each of the other players.
If two players say win and chow/pung/kong simultaneously, the win  takes precedence over another.
There can only be one winner and three losers in a hand. If more than one players declare win by a discarded tile, who is closest to the discarding player wins.
A player can only win by an own tile or robbing a kong when he/she can win by any tile, like an eye calling all pung hand with a wild tile.

Bottom stage and a draw

When there are 14 tiles left in the wall, the hand enters the bottom stage. In the bottom stage, each player draws one tile from the wall in his/her turn, and either wins or does not discard a tile if he/she does not. One cannot do a kong in the bottom stage. If no one wins in the bottom stage, or when the wall becomes 10 tile long, the hand ends in a draw.

Scoring

Each loser pays to the winner base point doubled by any applicable doubles.
The results are usually divided by 10 (which works well with the 8 point minimum, 20 might be better for minimum of 16 or higher) and rounded to a nearest whole number to make the settlement faster, so 8 becomes 1, 16 becomes 2, or 128 becomes 13 and so on.
Base point
It is determined by type of win, that is either major or minor:
  • minor win: 1 point
  • major win: 10 points for each applicable condition.
Some counts base of multiple major hands exponentially, like 10, 20, 40...

Major wins are:
  • Pure one suit (清一色). Four sets and a pair of eyes in one suit. Wild tiles can be substituted. It can have any single tile kong. The eye can be any tile (i.e. other than 2, 5 and 8).
  • All honors (风一色). All tiles are winds or dragons (but red). Wild tiles can be substituted. It can have any single tile kong. It must have at least one open sets, but the rest do not have to form sets nor is it necessary to have a pair of eyes.
  • All eyes (将一色). All tiles are 2, 5 or 8. Wild tiles can be substituted. It can have any single tile kong. It must have at least one open sets, but the rest do not have to form four sets nor is it necessary to have a pair of eyes.
  • All pung (碰碰胡). Four sets are pung. Free eyes.
  • All claimed (全求人). Four open sets (so closed kong doesn't count) and win by claiming a pair of eyes of 2, 5 or 8. It needs 2/5/8 as eyes to count as a major win.
  • Bottom tile (海底捞). When only 7 stacks/14 tiles are left in the wall, each player just draws a tile, and, if he/she wins, it is a win by a bottom tile, otherwise, he/she does not discard a tile. No one wins and 10 tiles are left, it is a draw. It needs 2/5/8 as eyes to count as a major win.
  • Kong bloom (杠上开). Win by own tile drawn for kong supplement. It needs 2/5/8 as eyes to count as a major win.
  • Robbing a kong (抢杠). It needs 2/5/8 as eyes to count as a major win.
Minor win is
  • Common win (平胡, 屁胡). Four sets and a pair of eyes. A set is a pung (or a kong) or a run of three tiles of a suit. An eye is a pair of identical tiles of 2, 5 or 8.

If a player has two or more wild tiles, he/she cannot win by a common hand even if these wild tiles are used at their face value. All but one must be discarded or kong'ed in such cases.

If a player has four open pung and only one tile left in his/her hand, the eye calling tile can be anything because it is all pung that does not require eyes of 2/5/8. But in order to score for all claimed as well as all pung, the last tile must be calling a pair of 2, 5 or 8.

Doubles

(a) in hands of winner and loser
  • Open sets (开口): one double. Some count one double for each open set
  • Open kong (明杠) and Red dragon kong  (红中杠): one double for eachA discarded Red dragon still counts as a kong. A robbed kong does not.
  • Closed kong (暗杠) and Wild kong (赖子杠):  two doubles for each. A discarded Wild tile still counts as a kong.
  • Banker (庄家): one double if minor, no double if major.
(b) winner only
  • Hard win (硬牌): one double. No wild tile or all wild tiles are used as its face value.
  • Own tile (自摸): one double if minor, half double (x1.5) if major. It does not  apply to kong bloom or bottom tile because they imply a win by own tile.
(c) loser only
  • Claimed (放冲): one double if minor, half double (x1.5) if major.

Example of scoring

A: banker, open
B: discarder, open
C: open, 1 Kong of red, 1 kong of wild tile
D: minor win, hard, open

A pays D: 1(minor base)x2(D's hard win)x2(D's open)x2(A's banker)x2(A's open)=16
B pays D:  1(minor base)x2(D's hard)x2(D's open)x2(B's discarder)x2(B's open)=16
C pays D: 1(minor base)x2(D's hard)x2(D's open)x2(C's open)x2(1 C's red kong)x4(1 C's wild kong)=64
D wins 16+16+64=96 points.

Liability

A liable player has to pay on behalf of the other two losers as well as him/herself.
All claimed liability: a player who was not ready and discarded the winning tile of an All claimed hand is liable.
Third open set of Pure liability: a player who discarded a tile for a third open set of a player who won a Pure One Suit is liable.
Robbing a kong liability: a player whose has his/her kong robbed is liable.

"Ready" here means a hand waiting for a valid win; i.e. with at least one open set and meeting minimum point requirement, a major hand if there are more than one wild tiles, and with eye of 2, 5 or 8 unless it is all pung, pure one suit, all honors, or all eyes. In particular, a hand is not ready if it needs Kong bloom or Robbing a Kong to be a valid win.

Limit

The limit is 300 points. If indivisual loser's score exceeds the limit, any points over the limit are ignored. When all three losers hit the limit, it is called "Golden limit" and the losers pay 400 points instead of 300. If a loser does not have an open set and hits the Golden limit, he/she has to pay "Radiant limit" of 500 points instead of 400. In a rare case when all the losers hit the Radiant limit, it is called "Trinity limit" and they all lose 600 instead of 500.

Variations

Red and Green kong (红中发财赖子杠). A popular variation in which Green dragons are kong tiles just like Red dragons. The limits are raised to account for more doubles, for example, normal one at 400, golden at 500, radiant at 600 and trinity at 700 or 800. Minimum points are usually set to 16 or 32 points.
Peel kong (皮子杠). Three tiles of the wild indicator and four tiles of one less than that in stead of Red (and Green) dragons are kong tiles called "peel" and treated just like Red dragons in the basic game. Red (and Green) dragons are normal tiles and can be used in pung, four tile kong or winning hands. The limits are adjusted just like in the Red and Green kong variant.
Double for each open set (口口番). Each open set counts as a double, both for winner and loser. Since it results in much higher scores, the limits are usually set at twice as high, limit at 600, golden at 800, radiant at 1000 and trinity at 1200, for example.

A Three-Player Version

There is a three-player adaptation of the game, attributed to the ancient city of Jingzhou. The differences are:
  • Deck: 96 tiles, with the Character suit and East wind are removed.
  • Walls: 16 tile wide, 2 tile high, one wall for each player.
  • Kong tiles: Red dragons are kong tiles. The wide-spread option of additional kong tiles is not used.
  • Minimum point requirement: set to 8, and one can win if at least one (not both) of the opponents satisfies it.
  • Bottom tile: as a major win does not exist, and consequently, the last usable tile in the wall for each player is treated just like any other ones (one can kong it, has to discard a tile). Last 10 tiles are left unused.
  • All Honours: with four sets and a pair is recognised to contain Pure One Suit as well as All Honours and All Pung.
  • Doubles: winning by an own tile and being claimed count as a full double (instead of a half) even in a major win.
  • Instant limit hands: All honours and All eyes are instant Golden limit, regardless of number of doubles.