Daisangen

Daisangen
Type	Yakuman
Kanji	大三元
English	Big three dragons
Value	Yakuman
Speed	Slow
Difficulty	Hard

Daisangen 「大三元」 is a standard yakuman. In English, it can be shortened to "DSG". This yakuman involves the collection of all three tile groups of the sangenpai (dragon tiles).

Tile pattern

Agari:

Note: This hand is also winnable with

, but this hand would be shousangen instead.

Development

Daisangen is one of the three yakuman gosanke 「役満御三家」, or "the three big families of yakuman", along with suuankou and kokushi musou. Of the three, daisangen is the only one that can be played open.

As the name implies, this yakuman depends on all three dragons. If at least two copies of a dragon tile are unavailable, then completing a triplet becomes impossible, thus preventing the yakuman.

Viability

Most instances of daisangen involve open calls for the dragon tiles. Therefore, one of the more reasonable hand states involve three pairs of the dragon tiles. That gives a player the opportunity to call on those tiles or at least have a shanpon tenpai involving one of the dragons. On occasion, a very lucky player could develop a completely closed hand with the yakuman embedded.

Sekinin barai

Main article: Sekinin barai

The rule of sekinin barai (i.e. pao) may apply to daisangen. It applies when a player has made open calls (pon/kan) with two of the dragons. When another player discards the third dragon, and that dragon is called so that all three dragons are in one hand, then the discarder is liable to pay for the yakuman.

If the yakuman hand wins via ron, the discarder and ronned player each pay half. If the yakuman hand wins via tsumo, the discarder pays the entire hand. This effectively punishes a player for guaranteeing a yakuman. However, even if the third dragon is called to complete a kan, sekinin barai still applies.