Chuuren poutou

Chuuren poutou
Type	Yakuman
Kanji	九連宝燈; 純正九蓮宝燈
English	Nine gates; Pure nine gates
Value	Yakuman (closed only)
Speed	Very slow
Difficulty	Very hard

Chuuren poutou 「九連宝燈」 is a yakuman and a specific instance to chinitsu. It contains the 13-tile pattern 1-1-1-2-3-4-5-6-7-8-9-9-9 of the same suit, plus any one more tile from the suit. A special pattern to a chuuren poutou tenpai produces one with a unique 9-sided wait. In this case, the winning hand is then called junsei chuuren poutou 「純正九蓮宝燈」, or pure chuuren poutou. The 13-tile pattern generates a 9-sided wait even as a normal hand with four sets and a pair. Chuuren poutou is therefore no hand shape exception, unlike chiitoitsu and kokushi musou.

Tile pattern

Regular

Agari:

Note: This hand can also win with . However, that would downgrade the hand to a mere chinitsu.

Nine tile wait

Agari: Any pinzu 1 through 9.

Value

Chuuren is a yakuman hand. However, while tenpai, some tile waits may actually award the hand for a considerably less value of haneman, as a closed chinitsu. Some rules award a double yakuman instead when the hand goes out from the 9-sided wait.

Development

The key to this yakuman is the possession of ankou of both 1's and 9's of one suit. If two of either group of tiles are not available, then any attempt at this yakuman is no longer possible. Of course, that is in addition to the collection of a string consisting of 2-8 tiles of the same suit. Since this hand uses a single suit, it overlaps chinitsu during development. In fact, many tenpai formations may result in chinitsu, rather than the yakuman. This is due to the ability of chinitsu to form some complicated waits.