Yaku compatibility

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A single hand composed of six yaku to produce a baiman hand.

This is a table showing the compatibilities of the different yaku with each other. While yaku may be combined in one hand, it is simply impossible to combine certain yaku with each other.

Alternatively, some yaku can always imply another. For instance, a junchan hand has a terminal in every group. This also fits the definition of chanta, which mandates that the hand has a terminal or honor in each group. Every junchan hand is also a chanta hand, so chanta is not scored. By rule, two yaku cannot be combined if one always implies the other. (A partial exception is with shousangen. Shousangen always implies two dragon yakuhai, but does not always imply you have any one of "haku", "hatsu", or "chun".)

Yaku

Key
Abbrevation Yaku
RCH Riichi
DRI Double riichi
IPP Ippatsu
SMO Mentsumo
TAN Tanyao
PFU Pinfu
IPK Iipeikou
ITT Ittsu
YAK Yakuhai
SDJ Sanshoku doujun
SDO Sanshoku doukou
TOI Toitoi
SNA Sanankou
SNK Sankantsu
CHA Chanta
JUN Junchan
RPK Ryanpeikou
SSG Shousangen
HRO Honroutou
HON Honitsu
CHN Chinitsu
CHI Chiitoitsu
RIN Rinshan
HAI Haitei
HOU Houtei
CHK Chankan

Yaku strategy involves viability to form yaku and maximizing hand value, if possible. This maximization often involves the recognition of the different yaku forming in one hand. Often, this affects the decision which tiles to keep and which to discard.

Three combinations actually form yakuman:

  • Toitoi + Junchan = Chinroutou
  • Toitoi + Mentsumo = Suuankou
  • Honroutou + Junchan = Chinroutou
  • Daburu riichi + Chankan is only possible with a Kokushi musou hand

Some combinations form a different yaku which implies one component of the combination, and as a result can never be counted:

  • Toitoi + Chanta = Toitoi + Honroutou
  • Chiitoitsu + Chanta = Chiitoitsu + Honroutou
  • Honitsu + Tanyao = Chinitsu + Tanyao
  • Honitsu + Junchan = Chinitsu + Junchan
  • Chinitsu + Chanta = Chinitsu + Junchan

These combinations are marked with in the table below.

Whether or not these combinations are actually combinations depends on the technical definition of the yaku. Some yaku are restricted versions of other yaku, such as junchan and chanta. There are two alternative ways to define this in the rules:

  • Chanta is scored when there are honors/terminals in each group, and requires that the hand contains at least one honor tile.
  • Chanta is scored when there are honors/terminals in each group (not requiring an honor tile). However, if a hand is eligible for both chanta and junchan, only one can be scored. Since junchan is the more valuable yaku, it is always the one scored.

Most of these combinations, with the exception of toitoi + mentsumo, are based on the assumption that the yaku are defined using the second method.

Nagashi mangan is excluded, because it is incompatible with anything, even riichi.

Compatibility

^ Ippatsu requires riichi to be of any use.

RCH DRI IPP SMO TAN PFU IPK ITT YAK SDJ SDO TOI SNA SNK CHA JUN RPK SSG HRO HON CHN CHI RIN HAI HOU CHK
RCH
DRI
IPP
SMO
TAN
PFU
IPK
ITT
YAK
SDJ
SDO
TOI
SNA
SNK
CHA
JUN
RPK
SSG
HRO
HON
CHN
CHI
RIN
HAI
HOU
CHK

Yakuman

Even different yakuman may be combined. As a result, point values may increase beyond single yakuman values as multiples of yakuman. Of course, that's only if the rules allow extension into double yakuman and beyond. Combinations involving three kinds of yakuman involve either tsuuiisou, tenhou, or chiihou. With this in mind, the options for combining different yakuman are limited.

Compatibility

KMU DSG SUA SSS DSS TSU RYU CHR CHU SUK TEN CHH
Kokushi musou KMU
Daisangen DSG
Suuankou SUA
Shousuushii SSS
Daisuushii DSS
Tsuuiisou TSU
Ryuuiisou RYU
Chinroutou CHR
Chuuren poutou CHU
Suukantsu SUK
Tenhou TEN
Chiihou CHH

External links