Honroutou

Honroutou

Type	Yaku
Kanji	混老頭
English	Terminals and honors
Value	2 han (consider as 4 han)
Speed	Slow
Difficulty	Hard

Honroutou 「混老頭」 is a standard yaku, focusing on just the honors and terminals. To score honroutou, the hand must contain only honors and terminals. The hand must contain at least one honor and one terminal; an all honor hand would be tsuuiisou, while an all terminal hand would be chinroutou.

Tile pattern

Agari: or

Formation

This yaku requires every tile to be a terminal or honor tile. Sequences are not allowed, because a sequence always contains non-terminal tiles. Naturally, a concentration of honor and terminal tiles are required to even consider this yaku. A majority of honroutou hands are open, using pon to complete a triplet-based hand.

Compatibility

Main article: Yaku 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

HRO

Honroutou is not compatible with any yaku which require a sequence, which accounts for most of the incompatibilities (including chankan, which must always win on a sequence wait). Tanyao is incompatible because it requires no terminals or honours, and honroutou requires only those tiles. Chantaiyao is incompatible because it is implied by honroutou. Finally, if honroutou is combined with junchan, the entire hand must be terminals, which gives the chinroutou yakuman.

Value

It is impossible to score this yaku without at least either toitoi or chiitoitsu. So this yaku is, at minimum, worth 4 han.

When factoring fu, the combination of ankou and minkou (closed and open triplets) produces a fu count of higher than 10. The lowest possible fu is generated with 4 minkou, leading to hadaka tanki (lone pair wait). Adding the base 20 fu for any hand, this yaku is guaranteed greater than 30 fu; and with the rules of fu, that number is actually rounded up to at least 40 fu. Therefore, a honroutou composed of ankou and minkou is at minimum a mangan.

Example:

Agari:

This is the second lowest possible honroutou, if not played in the West round. For each of the open calls, they are worth 4 fu. In combination, they add up to 16 fu. Then add the tanki (pair wait) for 2 fu. In total, this hand has 18 fu, in addition to the base 20 fu; and that makes 38 fu. Per the scoring rules, the number is rounded up to 40 fu. With a minimum of 4 han and 40 fu, this hand is guaranteed at least mangan when chiitoitsu is not involved.

The lowest scoring honroutou is a chiitoitsu won by ron without riichi or dora.

Example:

Ron:

This hand scores 4 han and 25 fu for 6400(9600) points.

External links

• 混老頭

Honroutou in Japanese Wikipedia