Tanyao
Tanyao 「断么九」 or 「断幺九」 is a yaku, obtained when the hand only has numbered tiles 2-8 from any of the three main suits. By proxy, the hand cannot contain terminal tiles (1 and 9) or honor tiles. It is one of the faster and easier yaku to obtain, though it is cheap. Depending on the ruleset, you may or may not be allowed to score this yaku when the hand is open.
| Type | Yaku |
|---|---|
| Kanji | 断幺九 |
| English | All simples |
| Value | 1 han |
| Speed | Very fast |
| Difficulty | Very easy |
The tiles numbered from 2-8 are classed as chunchanhai 「中張牌」, or simples. Therefore, this hand may be referred to as "All Simples" in English.
Tile pattern
Agari: or
-
Agari: 
or
As long as every tile is neither a terminal nor an honor tile, then the yaku is counted.
Kuitan
Kuitan 「喰い断」 is a rule allowing open tanyao. If kuitan is disallowed, then it would be specified as "kuitan nashi", and tanyao would be restricted as a closed only yaku. If kuitan is allowed, it would be "kuitan ari", and open tanyao would be allowed.
Tanyao takes special interest because it is fast, easy, and can be scored with many types of hand. With kuitan disabled, players are less likely to create cheap/fast 1-han hands.
Formation
In order to form a hand with tanyao, players simply discard terminal and honor tiles.
Even a hand cannot score tanyao, it's typically best to keep the "simple" tiles (2-8) over terminals/honors. This is because the simples are more likely to be useful.
- Lone honor tiles can only be used as a pair/triplet.
- A lone 1 can be used in a 123 sequence, or as a pair/triplet.
- A lone 3 can be used in a 123 or 234 or 345 sequence, or as a pair/triplet.
Because the 3 can be used in more types of sequences, it is more likely to be useful. Therefore, lone terminals/honors are often discarded first. Because terminals/honors are discarded early, hands may "naturally" form tanyao without the player needing any special effort.
It is might be unwise to force tanyao. If you already have a 789, for instance, then you probably shouldn't break the sequence. However, you may want to force tanyao if you need a fast hand (and the hand can be completed quickly).
Open tanyao enabled
With open tanyao allowed, tanyao becomes even faster to develop. While a tanyao-only hand is not worth much, it is often quick. If you need a win - e.g., to end the game faster, or to break a tie - then 1100 points may be all you need. In these cases, if tanyao is realistic, then call it. Depending on the hand, though, it may be faster to play yakuhai or (if the hand has completed groups with terminals) play closed.
You may also wish to play open tanyao if you have multiple (2+) dora. In this case, dora provide value on their own; tanyao + 3 dora is already mangan. Therefore, with multiple dora, you should call to speed up the already-valuable hand. If the dora are closed within the hand, then there is the added deceptiveness of your hand being a cheap hand, when in reality this is not the case.
Discard characteristics
As the hand looks to keep the simples, the discards will be the converse: terminal and honor tiles. As mentioned above, though, terminals/honors are often discarded even for hands without tanyao.
If a player has made multiple calls, none of those calls have a terminal or honor, and no other yaku is evident, then it is likely to be a tanyao.
Compatibility
^ Ippatsu requires riichi to be of any use.
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Naturally, tanyao is compatible with any yaku that does not utilize terminals or honors. The six yaku incompatible with tanyao all require such tiles in some way or another.
Tanyao is often combined with pinfu. The simple tiles are more likely to create sequences and more likely to create ryanmen waits. Therefore, hands aiming for pinfu will prefer simples, discarding terminals/honors, which can lead to tanyao.
Mentanpin
Mentanpin 「メンタンピン」 is short for a hand with riichi + tanyao + pinfu. "Men" stands for menzen (closed, and by extension, in riichi, not to be confused with menzen tsumo); "Tan" and "Pin" stand for tanyao and pinfu respectively. If the hand wins without riichi, then it is simply tanpin 「タンピン」.
With chinitsu and ryanpeikou
Some special optional yakuman are considered when in combination with chinitsu and ryanpeikou simultaneously.
- Pinzu (circles), dai sharin – 「大車輪」 or big wheels
- Souzu (bamboo), dai chikurin – 「大竹林」 or bamboo forest
- Manzu (characters), dai suurin – 「大数隣」 or numerous neighbours
These yakuman are awarded for having 22334455667788 in the same suit. This requires chinitsu and ryanpeikou, although this is not enough, as the hand 22334444556677 would qualify for tanyao, chinitsu, and ryanpeikou, but not for one of these yakuman.
Value
The speed of the hand's development justifies the value of the hand at 1-han. This speedy play is associated with cheap value. However, if red fives and/or other dora are incorporated, then a simple tanyao hand can easily become a very high-scoring one.
External links
- Tanyao in Japanese Wikipedia