Rule variations

Given the complexity to the rules of Japanese mahjong, the rules are even made more complicated by the existence of rule variations enforced among different groups and organizations.

Variation table

Rule	WoRR	Ema2	JpmlA	JpmlB	NPM	Skoui	SkouC	MuMa	RmuA	RmuB	RmuC	101	Tenho	Skyos	Korea	Uspml	Montr

Rulesets

• WoRR

Word Riichi Rules for the tourney in France, 2014. This ruleset is still in development. Not all details have been decided yet.

• Ema2

European Mahjong Association (EMA) Riichi Competition Rules (RCR) from 2012

• JpmlA

Japan Professional Mahjong League (JPML) ruleset A

• JpmlB

Japan Professional Mahjong League (JPML) ruleset B

• NPM

Nihon Pro Mahjong (NPM)

• Skoui

Saikouisen, the oldest Japanese professional league

• SkouC

Saikouisen Classic

• MuMa

Mu Mahjong

• RmuA

Real Mahjong Unit (RMU) ruleset A

• RmuB

Real Mahjong Unit (RMU) ruleset B

• RmuC

Real Mahjong Unit (RMU) ruleset C

• 101

Ruleset of 101, another Japanese league

• Tenho

Tenhou.net, a popluar internet game site

• Skyos

Saikyousen, a tournament in Japan run by Takeshobo

• Korea

Korean Mahjong League (KML)

• Uspml

United States Professional Mahjong League (USPML)

• Montr

Mahjong Montreal, Canada

Agari

Ryanhan shibari

Main article: Ryanhan shibari

Impose a two-han minimum at five or more honba (number of table counters). The two han must both come from yaku.

• Ari – Require two han from yaku at five or more honba.
• Nashi – One han from yaku is always enough.

Agari yame

Allow the dealer to end the hanchan prematurely if he wins the south 4th hand and ends up in first place, or if that hand becomes an exhaustive draw and the dealer ends up first.

• Ari – Allow the dealer to end the hanchan prematurely.
• Nashi – The game must continue until the seat winds rotate again.

Double ron

Score two winning declarations at the same time.

• Ari – Discarder of the winning tile must pay both hands separately. Riichi sticks are collected by the first winner to his right. Some rules entitle the other winner to one of these riichi sticks if he has declared riichi during this hand.
• Check – Like ari, but the fourth player must reveal a non-winning hand, so that he cannot intentionally avoid the triple ron abortive draw.
• Nashi – Atamahane, or head bump. Only the first win to the discarder's right is recognized.

Triple ron

Score three winning declarations at the same time.

• Ari – Discarder of the winning tile must pay all three hands separately. See double ron ari for distribution of riichi sticks.
• Ata.h. – Atamahane, or head bump. Only the first win to the discarder's right is recognized.
• Abort – Do not score any hand, instead abort the hand with an abortive draw (tochuu ryuukyoku).

Furiten riichi

Allow players to declare riichi while they are fuiten due to their own earlier discards.

Atozuke

Main article: Atozuke

Allow the hand to win even if there exists no yaku that is satisfied with all wait tiles. Atozuke nashi, also called sakizuke ari, requires all winning possibilities to satisfy at least one same yaku. Sakizuke requires some

• Ari – Atozuke: Allow determination of yaku after determining the winning tile.
• Nashi – Sakizuke: Require a fixed yaku no matter how the hand wins.

Chombo

Main article: Chombo

Wall toppling

What is the penalty for toppling tiles from the live wall?

• 6c – If six or more are toppled, then chombo is applied..
• Comp – This is a computer game. The rules infraction cannot occur.

Dead w. toppling

What is the penalty for toppling tiles from the dead wall?

• Ld6c – If you topple at least one tile from the dead wall, you get a dead hand. If six or more are toppled, then chombo is applied.
• Comp – This is a computer game. The rules infraction cannot occur.

Dora

Main article: Dora

Akadora

Use some red fives in place of normal fives as extra dora.

• Ari – Use three red fives, one per suit.
• Nashi – Don't use any red fives.
• Option – Tenhou.net offers both rules in different games. You can play akadora ari only if you if you play kuitan ari.

Uradora

Winning riichi declarers may flip the tile underneath the first dora indicator and treat that as another dora indicator.

• Ari – Flip the first ura dora indicator.
• Nashi – Don't flip it. Riichi declarers will know in advance how much their hand is worth.

Kandora

After declaring a kantsu, another dora indicator is flipped in the dead wall. All four players can benefit from this.

• Ari – Flip a new kan dora indicator after declaring a kantsu, but I don't know the exact timing rules.
• Sokun. – Sokunori. After declaring any type of kantsu, flip the next dora indicator immediately.
• Late – After declaring ankan (concealed kantsu), flip the next dora indicator immediately. After declaring a minkan (open kantsu per call on a discard or per extension of a minkou), flip the next dora indicator only after declaring tsumo, declaring another kan, or discarding. The new dora indicator is in effect for any type of win.
• Nashi – Don't flip any dora indicators upon declaring kantsu.

Kanuradora

Winning riichi declarers may flip the tile underneath each kan dora indicator and treat that as another dora indicator.

Fu

Counting fu may have some variation. A hand with four groups and a pair might have a double wind pair, by which the wind pair is both the round wind and the seat wind. This rule decides how many fu such a double wind pair is worth.

• Ari - The pair counts as 4 fu: 2 from the wind, and 2 from the wind round.
• Nashi - The pair only counts for 2 fu.

Kuikae

Main article: Kuikae

This allows a player to call pon or chii on a tile, then afterwards discard the same tile, or a tile which would have completed the two revealed tiles at the other end of the sequence (switching chii).

• Full – Allow to discard any tile.
• Swap – Forbid discarding the same tile, allow switching chii.
• Nashi – Forbid discarding the same tile, forbid switching chii.

Kuitan

Main article: Kuitan

Allow the 1-han yaku tanyao (all simples) to be awarded to an open hand.

• Ari – Allowed
• Nashi – Not allowed
• Option – Tenhou.net offers both rules in different settings. One of the game rooms is set for both kuitan nashi snd akadora nashi. However, there is no setting for one or the other exclusively. The Korean rules write "concealed hand only selective", which sounds as if kuitan were an optional rule.

Naki

Main article: Naki

Variation may apply on tile calls. If several players call chii, pon, or ron on the same tile, this rule decides who will get the tile. Kan calls are treated like pon calls.

• Pon – Like pon above, but keep in mind that this is a computer game (C), not a ruleset for live play.
• Time – Pon trumps chii if called at the same time, otherwise the first call stands. Ron trumps anything, even if called slightly later.

Pao

Main article: Sekinin barai

Daisangen and daisuushii

Impose a liability payment on the player who has dealt the third ponned dragon tile, or the fourth ponned wind tile, if the caller wins with daisangen (big three dragons) or daisuushii (big four winds) later.

• Ari – Liable player pays full on tsumo, half on ron.
• Nashi – No liability for daisangen or daisuushii.

Suukantsu

Impose a liability payment on the player who has dealt the fourth kanned tile, if the caller wins with suukantsu (four kantsu) later.

• Ari – Liable player pays full on tsumo, half on ron.
• Nashi – No liability for suukantsu.

Daiminkan

After forming a daiminkan (kan declaration on a discard with three concealed identical tiles), rinshan kaihou may be counted as a ron, against the discarder of the called tile. Thus, others are not held responsible for this play.

• Ari – Score the hand as a ron if won before the next discard.
• Nashi – Score the hand as a tsumo.

Scoring

Main article: Scoring

Scoring allows some flexibility to the rules regarding the start and end scores. Likewise, the oka and uma may be adjusted as well.

Start score

Each player has this many points at the start of a hanchan.

• 0 – Start at zero points, but the game continues with negative scores.
• 25k–30k – A negative score aborts the hanchan.

Goal score

Used at the end of a hanchan for the next two rules: If oka is used, first place gets a bonus payment, called the oka, of 3 × (goal − start score), paid evenly by the others. If shaaba is used, the game continues into the west round if no player has reached the goal score after the south round.

• Goal > Start – Oka may be paid, shaaba may used; see those rules.
• Goal = Start – Oka is zero, shaaba is never used.
• Tobi (bankrupt) - End the hanchan prematurely if a player has less than 0 points at the end of a hand.

Negative score

Main article: Hanchan

It is customary to end the game when a player falls below zero points. However, a game ending prematurely may not be desired, especially when the game is being televised. Therefore, in some rules, the game continues onward regardless.

• Ari - Game ends, when a player falls below zero points.
• Nashi - Game continues through the full progression of the game.

Oka

Jackpot for getting first. All three other players pay one third of this to first place after the end of the hanchan. These points are exchanged in addition to the uma.

Uma

This is a placing bonus for first and second place after a hanchan. First place receives (larger amount × 1,000) points from forth place, and second place receives (lower amount × 1,000) from third place. These points are exchanged in addition to the oka.

• 0 – No placement bonus is exchanged.
• Share – Ask Sylvain what this means in detail. I don't know. :-)
• X/Y – First place receives (X × 1,000) points from fourth place, second place receives (Y × 1,000) points from third place.

Shaaba

Main article: West round

If nobody has reached the goal score at the end of south 4th hand, then the game continues into the west round. The game immediately stops after any hand during the west round in which a player reaches the goal score. The game never continues into the north round.

• Ari – Continue into west round.
• Nashi – Always stop after south 4th hand.

Yakitori

Main article: Yakitori

Have players who do not win a hand during the entire hanchan pay a penalty to those who do, or to whoever is first. This rule is generally used in gambling games. As for the formal tournament setting, few, if any, actually use it.

• Ari - Yakitori penalty is applied.
• Nashi - Yakitori is not applied.

Kiriage mangan

Score 4 han, 30 fu as a mangan, as well as 3 han, 60 fu. The exact values for these hands are 7,700 points on a non-dealer ron, split as 2,000 and 3,900 on a non-dealer tsumo, and 11,600 points on a dealer ron, split as 3,900 for all on a dealer tsumo.

• Ari – Round up to mangan, i.e., score 8,000 or 12,000 points.
• Nashi – Score the exact values.

Leftover riichi points

If the last hand of the hanchan is a draw, there may be leftover riichi sticks on the table. This rule decides what happens with them.

• Lost – Nobody gets the leftover riichi sticks.
• Share – The players with the highest scores share the sticks equally. There is no information on how fractional sticks are handled for 3 or 4 tying players.
• Tiebr. – The table winner gets the sticks. If several players tie for first place, better places are assigned according to initial winds.
• Back – The sticks go back to the players who bet them.

Scorekeeping

Keep track of player's scores during a hanchan.

• Option – Each tournament can specify a suitable scorekeeping method.
• Paper – Scores are written down on a scoresheet.
• Tenbo – Scoring sticks (tenbo) are exchanged after each hand.
• Comp – This is a computer game and it keeps track of scores automatically.

Karaten tenpai

Main article: Tenpai

Karaten is a state where a hand in tenpai has all of its winning tiles exhausted via discards, dora indicators, open calls, kans, and even in other players' hands.

• Ari - The hand is tenpai under all karaten situations.
• Noten - The hand is declared as noten at ryuukyoku.
• Kan noten - The hand is declared as noten at ryuukyoku, if all of a player's waits are used for one's own kan. The hand is declared as tenpai for all other cases.

Renchan

Renchan are additional hands, where the wind rotation is not applied. Instead, the wind positions remain the same for an extra hand.

• Agari – The hand is repeated only when East wins.
• Tenpai – The hand is repeated when East wins, or when East is tenpai upon exhaustive draw.
• Nanba – The hand is repeated when East wins, or when East is tenpai upon exhaustive draw, or when there is any exhaustive draw during the nanba (south round).
• Option – The rules allow two possible options, agari and tenpai.

Tochuu ryuukoku

Main article: Tochuu ryuukoku

Abort a hand and repeat it at the next honba (number of table counters) in case of nine terminals and honors, same wind discards, four riichi declarations, or four kantsu declarations. Some rules abort the hand upon a triple ron; that is not covered by this rule, instead see triple ron.

• Ari – Abort and reshuffle in these situations.
• Nashi – Do not recognize any of these abortive criteria. Play every hand until a winning declaration or exhaustive draw. Do not allow a fifth kan declaration nonetheless.

Yaku

Main article: Yaku

Different yaku may be subject to rule variation. Some are simply not considered standard.

Ippatsu

Score an additional han for winning a riichi declaration within the next go-around.

• Ari – Score ippatsu as an extra 1-han yaku.
• Nashi – Don't score ippatsu.

Daburu riichi

Score riichi as 2 han yaku instead of 1 han if called within the first uninterrupted go-around of a hand.

• Ari – Score daburu riichi as 2 han instead of 1 han.
• Nashi – Always score 1 han per riichi declaration.

Open riichi

Allow players to declare open riichi instead of a normal riichi. Open riichi is worth 2 han instead of the normal 1 han. The declarer must reveal his hand at the same time as he pays the bet of 1,000 points.

• Ari – Allow open riichi along with normal riichi.
• Nashi – Don't allow open riichi.

Sometimes, directly playing into an open riichi (ron) is penalized by yakuman value.

Nagashi mangan

Score a mangan upon exhaustive draw for having discarding only yaochuuhai during the entire hand, with none of the yaochuuhai having been called by other players, and without having called any tiles oneself. If this is allowed, there are additional rules decisions necessary: Does it count as a win, or merely as replacement of the noten penalty? Are concealed kantsu allowed?

• Ari – Score nagashi mangan, but I don't know the details.
• Ari B – Score nagashi mangan as a replacement of the noten penalty, not as a fully-fledged win. I don't know what happens if you declare ankan, that will likely prevent nagashi mangan.
• Ari KW – Score nagashi mangan as a win (W), voiding noten riichi chombos and collecting riichi bets and honba payments. It is legal to declare a concealed kantsu (K) and still score nagashi mangan.
• Nashi – Don't allow nagashi mangan.

Haitei/houtei

Score the 1-han yaku haitei raoyue for winning with the last tile from the live wall, or score the 1-han yaku houtei raoyui for winning on a discard while the live wall is empty.

• Ari – Both yaku are allowed.
• Nashi – Neither yaku is allowed.

Haitei and rinshan

When a kantsu is declared with exactly one tile left in the live wall, that tile, called the haiteihai, is appended to the dead wall and never drawn. This rule makes the replacement tile the haiteihai, so winning with that tile scores both rinshan kaihou (winning after kan) and haitei raoyue (winning with the last tile).

• Ari – Allow this combination. I consider this a bug in the 2012 EMA RCR.
• Nashi – Do not allow this combination. This is Japanese default.

Kokushi and chankan

Main article: Kokushi musou

Main article: Chankan

Sometimes, it is allowable for a tenpai kokushi musou to declare ron on an ankan and thereby invoking the ability for chankan.

• Ari - Allowed
• Nashi - Disallowed

Tenhou/chihou

Score a self-drawn win within a hand's first uninterrupted go-around as a yakuman.

• Aari – Score tenhou and chihou as yakuman.
• Nashi – Score these wins as normal hands.

Renhou

This is a yaku for winning on a discard before the winner's first turn in an uninterrupted go-around.

• YMan – Yakuman: Score this as a yakuman. No other yaku is necessary.
• M – Mangan: Score this as a mangan. No other yaku is necessary.
• Yaku – Renhou functions as a regular yaku, with an assigned han value. As a regular yaku, it is capable of combining with other yaku.
• Nashi – Renhou is not a yaku. The hand is scored normally, there must be at least one other yaku present for a valid win.

Daisharin

Daisharin is an optional yaku. This involves pairs of the simples of the suit, pinzu. Sometimes it is regarded as a yakuman. Otherwise, the hand is counted normally with its yaku counterparts. The hand is at least 11 han with a combined chinitsu, ryanpeikou, and pinfu.

Agari:

• Ari – Score this hand as a yakuman.
• Nashi – Score this hand normally.

For souzu and manzu, the hands are labeled as daichikurin and daisuurin.

Paarenchan

Score the eighth consecutive win of the same dealer as a yakuman.

• Ari - Yakuman scored.
• Nashi - Eighth hand scored normally.

Kazoe yakuman

Score a hand with 13 han or more as a yakuman.

• Ari – Score as a yakuman with 8,000 basic points.
• Nashi – Score as a sanbaiman with 6,000 basic points.

Double yakuman

Score each of the listed patterns as a double yakuman.

• Nashi – All yakuman count as single yakuman. See combined yakuman below for another possibility to score a multiple yakuman.
• D – Daisuushii may be scored as double on its own, or else relegated to a single.
• S – Suuankou tanki may be scored as double on its own, or else relegated to a single.
• K – Kokushi musou shiisanmen machi : Thirteen orphans winning from the thirteen-sided wait on the pair.
• 9 – Junsei chuuren poutou : Nine heavenly gates winning from the nine-sided wait 1112345678999.

Different yakuman patterns may be combined. However, scoring is handled differently as well. Score more than one yakuman if multiple yakuman are achieved by the same hand.

• Ari – Add one yakuman per single yakuman, add two yakuman per double yakuman if allowed, and score the sum.
• Nashi – Score only one yakuman per hand, or two yakuman if double yakuman are allowed.

Rinshan fu

Award a hand winning with the rinshanpai (kan replacement tile) the usual 2 fu for winning with a self-drawn tile.

• 2 fu – Award the hand 2 fu for tsumo.
• Nashi – Don't count any fu for tsumo on the rinshanpai.

External links

Source page