Machi

Revision as of 15:19, 19 June 2024 by Hordes (talk | contribs) (update intro section & basic wait patterns - condense, improve english, add information on basic waits)

Machi 「待ち」, or "waits" in English, are patterns that can be used to form tile groups and/or pairs. They of are particular interest for tenpai hands, since a tenpai hand's wait determines which tiles it can win with.

There are 5 "basic wait patterns". These patterns are the most frequent: they are comprised of only 1-2 tiles, and are not dependent on anything else in the hand. Basic waits can be combined in order to form bigger, "complex waits".

Overview

Many different patterns arise during hand development. Once a hand is in tenpai, being able to recognize your winning tiles is important, lest you miss a win. The most common patterns are given names to make them more recognizable.

When a hand is in tenpai:

  • N-sided wait refers to the number of types of tile a hand can win with. A hand that waits for 1m and 4m would be 2-sided. The largest sided wait is kokushi musou, which has a 13-sided wait.
  • N-tiles available refers to the number of tiles a hand can win with. A hand that waits for 1m and 4m would wait for 8 tiles at maximum (4 copies of 1m, 4 copies of 4m). This number decreases if the winning tiles are discarded, visible in others' tile calls, or if the winning tiles are included in the hand. If a hand that waits for 1m and 4m already has two copies 1m, it would wait for 6 tiles at maximum. A hand can wait with 0 tiles remaining.

Understanding waits is important, even before reaching tenpai. Wait patterns are used to form tile groups, so a hand will gather many wait patterns before reaching tenpai. Keeping better waits in your hand will allow you to to complete your hand faster.

Basic wait patterns

There are five basic wait patterns. These are made out of 1 or 2 tiles. Upon tenpai, they only look to complete either the last tile group or the pair. All waits can be derived from the basic waits.

Romaji Kanji/Kana Translated Pattern No. Sides Max. tiles Fu
Ryanmen 両面 Open
              Waiting for:   
2 8 tiles 0 fu
Shanpon 双ポン Dual pair
              Waiting for:   
2 4 tiles 0 fu
Kanchan 嵌張 Closed/middle
              Waiting for:  
1 4 tiles 2 fu
Penchan 辺張 Edge
              Waiting for:  
1 4 tiles 2 fu
Tanki 単騎 Pair
              Waiting for:  
1 3 tiles 2 fu

Each of these wait patterns are also worth fu. For the purposes of fu counting, a complex wait can always be interpreted as one of the basic waits. (If multiple interpretations are possible, the highest scoring one is used. This may or may not be the one with the most fu.)

Named combinations

The basic patterns can be combined for more complex patterns; and the wait patterns listed here have taken on names.

Name Kanji/Kana Header text
Nobetan 延べ単
ノベタン
              Waiting for:   
Standard Sanmenchan 狭義の三面張
              Waiting for:    
Sanmentan 三面単
              Waiting for:    
Entotsu 煙突系
エントツ
              Waiting for:    
Aryanmen 亜両面
              Waiting for:   
Ryantan 両単
              Waiting for:    
Pentan 辺単
              Waiting for:   
Kantan 嵌単
              Waiting for:   
Kantankan 嵌単嵌
              Waiting for:    
Tatsumaki 竜巻
              Waiting for:      
Happoubijin 八方美人
              Waiting for:         

Double yakuman patterns

These two unique patterns are linked to specific yakuman. Under all possible tile waits with these patterns, yakuman is ensured; under some scoring rules, winning a hand with these patterns is awarded double yakuman. There are no other wait patterns with more than 8 winning tiles (although it is possible for an 8-sided wait to include four of the same tile in such a way that a hypothetical fifth copy of the same tile would complete the hand).

Chuuren poutou kyuumen machi

              Waiting for:          

Kokushi musou 13 machi

              Waiting for:              

Complex patterns

These combinations involve patterns that do not have specific names. Instead, they use combined forms of the other patterns. Furthermore, they mostly consist of consecutive, or closely consecutive, numbered tiles. Recognition of these patterns can produce some significantly powerful waits, which may be immune to suji and have large numbers of waiting tiles.

Related terminology

Karaten

Karaten 「カラテン」, or empty tenpai, is the case where there are no tiles left to win with, due to all potential winning tiles already having been used in the player's hand, a discard pool, a called group, or visible as dora indicators. In some rulesets, a hand in this state is considered noten at an exhaustive draw.

Takame and yasume

Takame is a potential winning tile which is worth more points than another, called yasume.

External links

Machi in Japanese Wikipedia
Forum list of various patterns
Wait survey quiz in Tenhou.net