|Value||1 han per counted triplet|
Yakuhai 「役牌」, or Fanpai 「飜牌」, is a group of 1 han yaku scored for completing a group of certain honour tiles. Along with tanyao and riichi, these yaku are the easiest and most frequently occurring yaku in the game. The yakuhai awarded for wind tiles are unique in that the eligible tiles change over the course of the game, relative to each player. Dragon tile groups, on the other hand, count throughout the game.
|East seat||自風 東||East round||場風 東|
|South seat||自風 南||South round||場風 南|
|West seat||自風 西||West round||場風 西|
|North seat||自風 北||Green dragon||役牌 發|
|Red dragon||役牌 中||White dragon||役牌 白|
All that is required for yakuhai is a single triplet or quad of an eligible tile. The three dragon tiles are always eligible, but among the wind tiles, only the round wind and the player's seat wind are eligible. Guest winds are ineligible.
Yakuhai is not a single yaku but rather a collection of five yaku (one for each dragon, one for the round wind, and one for the seat wind). The five are all compatible with each other and they can be scored in any combination, except that all three dragon yakuhai will lead to daisangen instead. If the round wind and seat wind are the same, then both are scored for that group.
The triplet of the green dragons satisfies the yaku regardless of seating and wind round.
Here, the triplet of the east wind satisfies the yaku if this hand is scored during the east round, or by the dealer in any round. In the east round, the dealer will score the double east wind as 2 han.
Each of the dragon quads scores 1 han for its own yakuhai. They are scored separately, and the fact that they are quads rather than triplets is irrelevant in the scoring. The additional pair of red dragons means that the hand scores shousangen in addition to, but not instead of, the double yakuhai.
Along with tanyao, yakuhai are among the easiest yaku to learn and use. As the honour tiles are generally weak due to their inability to form sequences, they are often discarded early in the hand. A player starting with a pair of eligible tiles can usually pon a third, instantly satisfying the yaku requirement. This ability makes this yaku exceptionally convenient for the completion of fast hands. Therefore, this yaku is also sometimes called an express ticket.
Players looking for a quick win will often hold lone yakuhai tiles a little longer than their tile efficiency would dictate, in hopes of getting a second and then calling (or drawing) a third to make a yakuhai. This is particularly true with hands that will have difficulty completing an open tanyao, either because they have lots of terminals or honours, or because open tanyao is not allowed.
Yakuhai hands may commonly be used for atozuke. Here, the hand depends on yakuhai for yaku, where among the multiple waiting tiles, one of them is a yakuhai tile. However, the other waiting tile(s) may not produce a yaku, unless it wins via chankan, rinshan, haitei, or houtei.
While yakuhai can be referred to collectively and it is rarely ambiguous, it is not uncommon to call them out individually, particularly when scoring a hand by announcing its yaku. The table to the right shows the written forms of most of the yakuhai.
For example, a dealer winning the previous hand during the east turn wouldn't say: "three yakuhai", but rather: "double east, red dragon". This makes the origin of each han clearer.
Yakuhai essentially works with any yaku which has room or allows the use of honor tile groups, which gives it great versatility. Honitsu is one of the most effective combinations with at least one yakuhai group. This yaku is compatible with itself. Different groups of yakuhai tiles may be collected into one hand; and in turn, they are treated as separate yaku, despite identical functionality. In particular, shousangen requires not just one, but two yakuhai.
Incompatibilities arise for a few reasons. Firstly, the definitions of tanyao, junchan, and chinitsu eliminates the use of honor tiles all together. Pinfu and ryanpeikou each require four sequence groups and chiitoitsu requires seven distinct pairs, leaving no room for a triplet in any of these yaku.
- Yakuhai in Japanese Wikipedia