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(note on why chanta is bad to go for) |
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By definition, every [[mentsu|tile group]] must include a [[terminal]] or [[jihai|honor]] tile. So combinations of tile groups involving 1-2-3, 7-8-9, 1-1-1, 9-9-9, and/or any honor [[jantou|pairs]]/[[koutsu|triplet]] qualify for chanta. | By definition, every [[mentsu|tile group]] must include a [[terminal]] or [[jihai|honor]] tile. So combinations of tile groups involving 1-2-3, 7-8-9, 1-1-1, 9-9-9, and/or any honor [[jantou|pairs]]/[[koutsu|triplet]] qualify for chanta. | ||
=== | === Compatibility === | ||
While chanta can be seen as the converse of [[tanyao]], chanta is | {{main|Yaku compatibility}} | ||
{{Yaku compatibility table|CHA}} | |||
Chanta's pattern is similar to [[junchan]]; however, the two can never combine as junchan implies a chanta hand. [[Honroutou]] likewise implies chanta and is thus incompatible. Chanta with [[toitoi]] or [[chiitoitsu]] actually forms honroutou instead of chanta, while chanta with [[chinitsu]] is actually junchan instead of chanta. | |||
Chanta is incompatible with [[tanyao]] and [[ittsu]] because both of those require a group which is not a terminal or honour -- in tanyao's case, it is required of all tiles in the hand, and for ittsu, a 4-5-6 sequence is needed. | |||
==Development== | |||
While chanta can be seen as the converse of [[tanyao]], chanta is much slower. This yaku is rarely seen in riichi mahjong, due to a few reasons: | |||
'''1. Smaller tile acceptance''' | |||
Middle tiles are more [[tile efficiency|efficient]] than terminals/honors for hand development. This can be measured by [[Ukeire|tile acceptance]] - the more tiles that can be used to form a sequence/pair/triplet, the higher the tile acceptance, and the more efficient the tile (generally) is. | |||
*A lone honor tile can only be used in a pair/triplet. Therefore, a lone honor only accepts itself. | *A lone honor tile can only be used in a pair/triplet. Therefore, a lone honor only accepts itself. | ||
*A lone 1 accepts 1, 2, or 3. There is no way to get a | *A lone 1 accepts 1, 2, or 3. There is no way to get a ryanmen wait off with a lone 1. | ||
*A lone 5 accepts 3, 4, 5, 6, or 7. There are two ways to get a ryanmen wait (45, 56). | *A lone 5 accepts 3, 4, 5, 6, or 7. There are two ways to get a ryanmen wait (45, 56). | ||
'''2. Cannot use [[ryanmen]] waits''' | |||
A "[[ryanmen]]" is two consecutive tiles waiting to complete either side of a sequence, such as {34}, {45}, {78}. Terminals can never be part of a ryanmen shape - {12} and {89} are not ryanmen. A ryanmen has twice the acceptance as any other type of [[Machi#Basic_wait_patterns|basic wait]]. | |||
Chanta can technically can use ryanmen, via {23} and {78}. However, it is only half as effective, as you only get chanta with 1/2 of the winning tiles (1 and 9, respectively). Therefore, since chanta cannot use ryanmen, it is slower to develop than a regular hand. Plus, in order to guarantee chanta in [[tenpai]], your hand must have a bad wait (<= 4 tiles left in the wall). | |||
{{ | |||
'''3. Not valuable''' | |||
Since chanta is so slow, and only worth 2 han (even less when opened), it usually isn't worth the effort. Even without considering [[riichi]], there are easier ways to get 2 han, such as tanyao + [[pinfu]], pinfu + 1 dora, pinfu + [[iipeikou]], and so on. Therefore, players will rarely go for chanta. Chanta is even less common when [[red five]]s are used, since tanyao + 1 aka dora is already worth as much as chanta. | |||
Chanta is | Chanta can be good to aim for when: | ||
*You need a quick hand, and chanta/junchan is your only realistic way your hand can complete open. | |||
*You happen to get most of the required tiles already (e.g. 123 [[sanshoku]] with other terminals/honors mixed in). | |||
*You were going for [[kokushi musou]], but kokushi became impossible early in the round, and you are desperate to win. | |||
==External links== | ==External links== |
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