Ikkitsuukan: Difference between revisions

m
m (Undo revision 11237 by KyuuAA (talk))
(21 intermediate revisions by 7 users not shown)
Line 10: Line 10:
* [[Iipeiko]]
* [[Iipeiko]]
* [[Chinitsu]]
* [[Chinitsu]]
|gameExample = * [http://tenhou.net/0/?log=2013010402gm-0009-7447-x1ba0b4910bee&tw=3&ts=7 Closed ittsu]
|gameExample = * [http://tenhou.net/0/?log=2013010402gm-0009-7447-x1ba0b4910bee&tw=3&ts=7 Closed ittsuu]
* [http://tenhou.net/0/?log=2014030918gm-0089-0000-22ae5fde&tw=2&ts=6 Ittsu] as [[kazoe]]
* [http://tenhou.net/0/?log=2014030918gm-0089-0000-22ae5fde&tw=2&ts=6 Ittsuu] as [[kazoe]]
}}
}}
'''Ikkitsuukan''' {{kana|一気通貫}}, or '''Ittsu''' {{kana|一通}} for short, is one of the standard [[List of yaku|yaku]]. This hand consists of three melds in one suit of 1 through 9, any available extra meld, and any pair. This hand may be open or closed.
'''Ikkitsuukan''' {{kana|一気通貫}}, or '''ittsuu''' {{kana|一通}} for short, is a [[List of yaku|yaku]], defined as three distinct [[mentsu|tile groups]] containing 123, 456, 789 of one suit. Collectively, the three groups form a complete single suit straight of 1 through 9. Naturally, in English terms, this hand can also be noted as a "straight", similar to the poker hand of the same name. This hand may be played open or closed.  When open, the hand [[Kuisagari|loses value]] of one han.


==Tile diagram==
==Tile diagram==
Line 19: Line 19:


===Open===
===Open===
{{#mjt: 222m46s55z}} {{#mjt: 1"23s}} {{#mjt: 8'79s}} Winning tile: {{#mjt: 5s}}
{{#mjt: 222m46s55z}} {{#mjt: 1'23s}} {{#mjt: 8'79s}} Winning tile: {{#mjt: 5s}}


==Formation==
==Formation==
While the hand shows a complete 1-9 grouping from a particular suit, it is best to view as three separate groups of: 123, 456, and 789.  This is particularly useful to note when needing to open the hand with such a combination.
While the hand shows a complete 1-9 grouping from a particular suit, it is best to view the long cluster as three separate groups of: 123, 456, and 789.


===Counter example===
===Counter example===
{{#mjt:12344m56p}} {{{{#mjt:5'677'89m}} Waiting for: {{#mjt:4p}} or {{#mjt:7p}}
Having all the tiles from 1-9 in one suit is not sufficient to compose this yaku - they must form as sequences of 123, 456, 789.


In this counter example, the tiles 1-9 for one suit are in the hand.  However, ittsu would not be counted.  In fact, this hand is lacks any yaku.  The manzu are not grouped as 123, 456, and 789.  Instead, they are grouped as 123, 567, and 789.
{{#mjt:12344m56p}} {{#mjt:5'677'89m}} Waiting for: {{#mjt:4p}} or {{#mjt:7p}}


=== Compatability ===
In this counter example, the tiles 1-9 for one suit are in the hand, but ittsuu would not be counted.  Instead, they are grouped as 123, 567, and 789, with 4-man functioning as the [[Jantou|pair]].
{{main|Yaku compatability}}


{{yakuheader}}
==Discard characteristics==
| ITT || {{yes}} || {{yes}} || {{yes}} || {{yes}} || {{no}} || {{yes}} || {{yes}} ||bgcolor="000000"| || {{yes}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{no}} || {{yes}} || {{yes}} || {{no}} || {{yes}} || {{yes}} || {{yes}} || {{yes}}
Hands aiming for ittsu often lack a particular suit, as a good number of one suit is collected in the hand.
|}
 
== Compatibility ==
{{main|Yaku compatibility}}
 
{{Yaku compatibility table|ITT}}
 
This yaku only leaves room for one tile group of any type, such as a triplet. Therefore, any yaku that requires more than one triplet, including [[sanshoku doukou]], [[toitoi]], [[sanankou]], [[sankantsu]], and [[shousangen]], is deemed incompatible. [[Chiitoitsu]] is likewise incompatible as it does not use [[mentsu]]. [[Tanyao]], [[chanta]], [[junchan]], and [[honroutou]] are incompatible as the 456 group contains no terminals or honours, but the 123 and 789 groups contain terminals. Finally, ittsuu is incompatible with [[sanshoku doujun]] and [[ryanpeikou]] as they each require at least three sequences in a way that are incompatible with the sequences used for ittsuu.
 
=== With sanshoku ===
{{main|Ittsu vs sanshoku}}
Ittsuu requires three out of the four tile groups to be composed of sequences: 123, 456, and 789.  Sanshoku also requires at least three groups of sequences.  Sometimes, a hand may be 1-shanten from either yaku because of composition.  There comes a point where a player may need to choose one yaku over the other, depending on the circumstances.
 
=== With pinfu ===
[[Pinfu]] requires a [[machi|wait pattern]] consisting of [[ryanmen]] (open wait) or a related wait like [[ryanmenten]] (three sided open). If a hand is waiting to complete the 1-9 pattern, a ryanmen wait would be subject to [[takame and yasume]]: only one tile would complete the ittsu.
 
However, this problem is completely averted if the hand already contains the full 1-9 pattern, with a wait depending on the extra tile group.
 
=== With honitsu and chinitsu ===
Ittsuu already contains nine tiles (1-9) of a single suit, so [[honitsu]] and [[chinitsu]] naturally combine with ittsuu. To form those yaku, the remaining four tiles (plus one winning tile) have to be composed of the same suit or an honor tile.
 
With closed hands, this combination produces some very powerful hands. With honitsu, the hand produces [[mangan]]; while it is [[baiman]] with chinitsu.


==External links==
==External links==
1,696

edits