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{{Infobox yaku | |||
|type = Yaku | |||
|kanji = 立直 or リーチ | |||
|english = Ready hand | |||
|value = 1 han (closed only) | |||
|yakuSpeed = Varies | |||
|difficulty = At discretion | |||
|yakuCombine = * All standard yaku | |||
* May be used with yakuman, but does not affect score | |||
|gameExample = * [http://tenhou.net/0/?log=2013080615gm-0009-7447-xa503715f0f66&tw=3&ts=5 With ippatsu] | |||
* [http://tenhou.net/0/?log=2013053111gm-0009-0000-d06067c3&tw=1&ts=4 Three riichis called] | |||
* [http://tenhou.net/0/?log=2013101121gm-0009-7447-372f7d30&tw=3&ts=5 Ippatsu oikake riichi] with "[[dora|dora bomb]]" | |||
* [http://tenhou.net/0/?log=2012120515gm-0009-7447-637daef9&tw=3&ts=3 Double riichi] | |||
}} | |||
'''Riichi''' {{kana|立直}} or {{kana|リーチ}} is the most common [[List of yaku|yaku]] in the game, occurring in ≥40% of winning wands across various platforms and professional settings. Any closed hand that is in [[tenpai]] can choose to declare riichi, gaining this yaku. | |||
Declaring riichi is not mandatory. Players may decline to declare riichi, keeping the hand's tenpai status hidden - this is a tactic known as [[damaten]]. Various game scenarios should be considered before calling riichi, such as current point standing and available tiles. | |||
== | == Rules == | ||
Riichi may be declared when: | |||
* The hand is closed - no [[chii]], [[pon]], or open [[kan]] has been made. | |||
* The hand is [[tenpai]] - it is one tile away from winning. | |||
* The player must have at least 1,000 points (assuming the player is [[Rule_variations#Scoring|not allowed to go into negative points]]). | |||
* There must be at least 4 tiles left in the live wall. In other words, the player must be able to draw at least one more tile in an uninterrupted set of turns. | |||
To declare riichi, a player announces riichi and discards a tile facing sideways in the discard pile. This is done to indicate when riichi was called. If that tile is claimed by another player for an open meld, then the next discard is turned sideways as a replacement. | |||
==Double riichi== | Unless the first sideways discard is claimed for a win immediately, the riichi announcer now places a bet of 1,000 points on the table. This bet is collected by the next player to win a hand. Specific rules will differ on what happens if multiple players win, or what happens if the game ends before any player claims the bet. | ||
Double riichi is a special case for riichi, | |||
After a riichi declaration, the hand remains locked and unchangeable. In this state, the player is simply waiting for a winning tile to appear, either by draw or discard. However, there is a notable exception: a riichi player may declare [[kan]] in [[#Kan|certain circumstances]]. | |||
In addition to the 1 han from riichi itself, you can score further han through [[#Ippatsu|ippatsu]] and [[#Uradora|ura dora]]. | |||
=== Kan === | |||
{{main|Kan#Kan during riichi}} | |||
You are able to declare a closed [[kan]] after a riichi. When this is legal will depend on the ruleset; improper calls may be subject to [[chombo]]. See [[Kan#Kan during riichi|Kan during riichi]] for more details. Even if the kan is legal, you may or may not want to declare one. | |||
=== Furiten === | |||
{{main|Furiten}} | |||
During riichi, a player may be furiten. In this case, the riichi is considered to be a '''furiten riichi'''. | |||
In addition, riichi hands are subject to a special type of furiten. After calling riichi, a player may decline to call on a winning tile. However, if a win is declined, then the riichi hand is subject to furiten for the remainder of the round. Thus, all tiles discarded after the riichi declaration (as indicated by the sideways tile) are considered to be guaranteed [[genbutsu|safe tiles]]. While it is advised to declare a win on the first opportunity, some plays may require a player not to do so under very specific circumstances. Of course, such play requires caution. | |||
=== Suucha riichi === | |||
{{main|Tochuu ryuukyoku}} | |||
Suucha riichi (4 player riichi) is an [[abortive draw]] that occurs when four players have declared riichi. After the fourth riichi declarer discards a tile, if that tile is not called for a win, the hand ends. | |||
===Noten riichi=== | |||
In real life play, a player may declare riichi without tenpai - this would be a '''noten riichi''' {{kana|ノーテンリーチ}}, which is highly ill-advised. If the hand results in [[ryuukyoku]], then it is required to reveal the hand. The hand would naturally show noten, which is illegal, and thus subject to a [[chombo]] penalty. Likewise, an incorrectly called win would also be subject to chombo. This dubious situation can be escaped if another player wins, another player commits a chombo, or if an [[abortive draw]] occurs. Of course, most computer based play will prevent players from declaring a riichi without tenpai. | |||
== Scoring == | |||
Two yaku are specifically associated with riichi: '''ippatsu''' and '''double riichi'''. In addition, '''ura dora''' may be scored for any winning riichi hand. | |||
=== Ippatsu === | |||
{{main|Ippatsu}} | |||
'''Ippatsu''' {{kana|一発}} is a separate yaku, but it is dependent on riichi. If, after declaring riichi, the hand wins before the declarer's next discard, then the hand scores ippatsu. Any [[Naki|tile calls]], including a player's own closed [[kan]], will invalidate ippatsu. | |||
=== Uradora === | |||
[[Image:Uradora.png|250px|right|thumb|The benefits of uradora. [http://tenhou.net/0/?log=2014070812gm-0009-7447-daa26980&tw=3&ts=9]]] | |||
{{main|Dora}} | |||
When a riichi declarer wins, the tiles underneath the [[dora]] and kan dora indicators are flipped over. These flipped ''ura dora indicators'' reveal the ura dora, which, like regular dora, may increase the hands value. | |||
=== Double riichi === | |||
{{main|Double riichi}} | |||
'''Double riichi''' {{kana|ダブルリーチ}} is a special case for riichi. If riichi is declared on the first turn, before the player's discard, then double riichi applies. In addition, no tile calls may have been made before riichi is called. As the name implies, double riichi is worth 2 han instead of 1 han, as a bonus for the initial timing. Due to the added han, and because tenpai is reached on turn 1, a double riichi hand has a huge advantage over others. | |||
=== Open riichi === | |||
'''Open riichi''' {{kana|オープン立直}} is an [[optional yaku]] which is a modified version of riichi. The mechanics are identical to a normal riichi, except that you must reveal either your entire hand or its tile [[wait]]s (depending on ruleset). In exchange, an open riichi is worth 1 extra han. Open riichi makes it trivial for other players to defend against your hand, so in general, the intent is to win by self-draw. | |||
As a further optional rule, yakuman may be awarded if any player intentionally [[ron|plays into]] the open riichi. If a player unintentionally deals in, i.e. if a riichi player deals into an open riichi, the yakuman is not scored. | |||
Many official organizations and tournaments do not implement any form of open riichi; it is more or less reserved for casual or gambling game settings. | |||
== Compatibility == | |||
{{main|Yaku compatibility}} | |||
{{Yaku compatibility table|RCH,DRI}} | |||
Given the rules, riichi is compatible with all other yaku. Likewise, riichi and double riichi cannot be combined as they are essentially the same yaku. It just happens that double riichi is a specific instance of riichi. Per rule and definition, it is impossible to attain ippatsu without riichi. | |||
Once again, the prospect for [[rinshan kaihou]] to work with riichi is dependent on the legality of the [[Riichi#Kan_during_riichi|kan call during riichi]]. With computer interfaces, this rule may be enforced by disabling a player's ability to call the kan during this situation. However, with actual tiles, a player must be aware of this legality. Otherwise, chombo may be enforced instead. | |||
== Strategy == | |||
{{main|Riichi strategy}} | |||
Calling riichi is an optional play. Therefore, players often have to make various considerations when it comes to using riichi. Often, this will depend on the discarded tiles, how early or late in the hand, the hand value, and/or the player's hand composition. If possible, a player may opt not to use riichi at all and instead employ the strategy of [[damaten]]. | |||
=== Oikake riichi === | |||
For any given hand, more than one player may call riichi. Subsequent riichi calls after the first is called '''oikake riichi''' {{kana|追いかけリーチ}}, or "chasing riichi". Oikake has one distinct advantage of an ippatsu ron chance against any previous riichi hands before taking a draw. After all, defense is no longer a factor to those hands, as they are committed to discarding non-winning tiles. The hands are essentially engaged in a "riichi duel" provided that they have different waiting tiles. Under many rulesets, the hand aborts in the event for all players to have declared riichi via [[suucha riichi]]. | |||
=== Karaten riichi === | |||
Riichi may actually be called if all waiting tiles are rendered unavailable. A hand in this state is rendered as [[karaten]]. In this state, the hand is not winnable as the number of available winning tiles is zero. Such calls may be made by mistake, or intentionally invoked to cause players to defend. | |||
==External links== | |||
{{jpwiki|立直}} | |||
* [http://osamuko.com/yaku-hai-riichi/ Yaku, Hai!: Riichi (& Ippatsu & Daburu Riichi)] | |||
: [http://osamuko.com/ Osamuko] article on riichi. | |||
[[Category:Yaku]] | |||
[[Category:Game rules]] | |||
{{Navbox yaku}} | |||