Kokushi musou

Kokushi musou

Type	Yakuman
Kanji	国士無双 国士無双１３面待ち
English	Thirteen orphans
Value	Yakuman (closed only)
Speed	Slow
Difficulty	Hard

Kokushi musou 「国士無双」, also simply known as kokushi, is one of the standard yakuman hands. This hand consists of one of each terminal tile from each suit and one of each honor tiles. The 14th tile must be a duplicate of any terminal or honor tile. If a player draws the thirteen different tile types before pairing any of them, then the hand is of the 13 wait variety, junsei kokushi musou 「国士無双１３面待ち」. This hand is one of the two exceptions of the "four melds and one pair" rule of forming a hand, where the other exception is the chii toitsu. This hand is closed only.

Tile diagram

Kokushi musou single wait

Winning tile:

Kokushi musou 13-way wait

Winning tile: Any one of the tiles shown here

• Winning from this wait is worth two yakuman in some rules.

Meaning and usage

The word kokushi can be translated as "distinguished citizen"; the word musou is often translated as "peerless". The word kokushi should not split up and expressed as "Koku shimusou". This is an incorrect spelling.

Development

Restricted as closed only, this hand must draw at least 12 of the 13 tile types, among the honors and terminals. If a pair exists within the hand upon tenpai, then naturally, the hand is waiting on the last remaining tile type not yet in the hand. In turn, this hand will be deemed impossible for completion, when all 4 of any of the tile types are no longer available. Yet, if a player manages to develop the 13 wait variety, then this hand greatly increases its chances of completion, needing to simply pair any of the 13 types.

Reasonable development of this hand begins with a dealt set of tiles that gives a player the option to call kyuushuu kyuuhai. Declining this option puts the hand on the path to form this yakuman.

Kyuushuu kyuuhai

Main article: Tochuu ryuukoku

Realistic chances to complete kokushi musou may require a hand to begin with at least 9 yaochuhai. Even so, at this point, this gives a player the option to defer and abort the hand, rather than trying for kokushi.

Attempting kokushi

Sample successful attempts

Kyoku	Yaochuhai start	Discard at tenpai	Result	Lobby	Link
東局２本場１	9	9th	Ron after 12th	上級	[1]
東局２本場１	9	6th	Ron after 6th	7447	[2]
南局３本場０	10	4th	Ron after 5th	鳳凰	[3]
東局１本場２	8	15th	Haitei ron	特上	[4]
南局４本場０	7	11th	Ron after 12th	上級	[5]
南局２本場０	11	2nd	Ron after 2nd	7447	[6]
Yaochuhai start includes the initial draw.

Any player attempting kokushi musou makes the decision at the beginning of the hand. This decision stems on a couple conditions, by which the primary decision rests on the number of unique yaochuhai at the start. The points and the current hand also influences the decision.

Value

This hand is a yakuman hand. Some rules may apply double yakuman for the 13-wait variety.

Chankan rule variation

Case where a closed kan was declared during a kokushi tenpai.

A kokushi tenpai hand may be awarded a win via chankan, if another player calls an ankan (closed kan) with that particular winning tile. Thus, ron may be declared in that instance. This is the only case where a tile may be taken from an closed kan. However, this particular rule may be subject to variation, which may or may not allow the play to occur.

External links

• 国士無双

Kokushi musou in Japanese Wikipedia

• Kokushi advice

Osamuko.com entry on Kokushi