Riichi: Difference between revisions

Riichi
Type	Yaku
Kanji	立直 or リーチ
English	Ready hand
Value	1 han (closed only)
Speed	Varies
Difficulty	At discretion

VisualWikitext

Latest revision as of 21:00, 24 March 2024

Riichi 「立直」 or 「リーチ」 is the most common 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.
If the game ends when a player has a negative score, the player must have at least 1,000 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.

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.

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 certain circumstances.

In addition to the 1 han from riichi itself, you can score further han through ippatsu and ura dora.

Kan

Main article: Kan#Kan during riichi

Kan during riichi is a discretionary play. Players must take note of the hand composition to determine whether the kan is allowable or not. If the call alters the hand's waiting pattern or alters the hand's composition, kan is not allowed. Improper calls are subject to chombo if detected.

Furiten

Main article: 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 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 article: 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 「ノテン立直」, 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 article: Ippatsu

Ippatsu 「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 tile calls, including a player's own closed kan, will invalidate ippatsu.

Uradora

Main article: 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 article: Double riichi

Double riichi 「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 「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 waits. 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 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 article: Yaku compatibility

^ Ippatsu requires riichi to be of any use.

	RCH	DRI	IPP	SMO	TAN	PFU	IPK	ITT	YAK	SDJ	SDO	TOI	SNA	SNK	CHA	JUN	RPK	SSG	HRO	HON	CHN	CHI	RIN	HAI	HOU	CHK
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 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.

Double riichi

Double riichi has the same compatibility as riichi, except for chankan. This is because, for a regular hand, chankan may only be formed from an added kan, which itself requires a call for pon to happen first.

If the pon call happens before the riichi call, then double riichi is negated.
If the pon call happens after the riichi call, then the double riichi player must have declined their winning tile, invoking furiten. Chankan can only be won from ron, so furiten prevents chankan entirely.

An exception is the yakuman kokushi musou. Depending on rule variation, kokushi may be won off a closed kan, which does not require a previous pon call. Therefore, in order to win with double riichi + chankan, it must also have kokushi. Since this would be a yakuman hand, the yaku of "chankan" is never actually scored.

Strategy

Main article: 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 「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

立直

Riichi in Japanese Wikipedia

Yaku, Hai!: Riichi (& Ippatsu & Daburu Riichi)

Osamuko article on riichi.

@@ Line 14: / Line 14: @@
 }}
-'''Riichi''' {{kana|立直}} or {{kana|リーチ}} is the most commonly used [[List of yaku|yaku]] in the game.  Among the yaku, riichi occurs at least 40% of the time across different mahjong platforms and professional settings.  This yaku may apply to any closed hand and [[Naki|may be declared]] upon achieving [[tenpai]].  As such, riichi is attainable via numerous hand configurations, as long as it is closed.  Due to its common usage, various specific game scenarios must be considered when using riichi, or facing [[defense|opponents who have called 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.
-Unlike other yaku, the call for riichi operates at a player's discretion and is certainly not mandatory.  Players may simply opt not to call riichi and retain the secrecy of a hand's tenpai status, using a tactic known as [[damaten]].  The decision for using riichi rests on some factors, primarily on need or desire.  Current point standings often factor towards a riichi call, especially when falling behind in points.  On the other hand, point leaders may tend to be conservative to limit opportunities for other players [[ron|to score hands directly]].
+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.
+* If the [[Rule_variations#Scoring|game ends when a player has a negative score]], the player must have at least 1,000 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.
-When a player has a closed tenpai hand, the player may declare riichi.  Doing so gains the hand 1 han.  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.
+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.
-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. Of course, a player must also have 1,000 points to begin with, assuming that a [[Rule_variations#Scoring|game ends with negative scores]].  Specific rulesets may handle differently what happens to the bet on a multiple win.
+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.
-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, a notable exception may involve calls for [[kan]].
+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]].
-It is not allowed to declare riichi when less than four tiles remain in the wall. The player must be able to draw one more tile in an uninterrupted set of turns.  For any hand, the absolute last chance to call riichi is when the player has a chance to score riichi, [[haitei]], [[ippatsu]], and [[mentsumo]].
+In addition to the 1 han from riichi itself, you can score further han through [[#Ippatsu|ippatsu]] and [[#Uradora|ura dora]].
-===Noten riichi===
-A player may actually declare riichi with a [[Tenpai|noten hand]].  This is a '''noten riichi''' {{kana|ノテン立直}}, which is highly not advisable.  Of course, computer based play is usually programmed to prevent players from making such a riichi declaration.  If and when the hand results in [[ryuukyoku]], then it is required of the player to reveal the hand to show tenpai.  The noten riichi would naturally show noten; and it is subject to [[chombo]].  Likewise, chombo is applied if a win is called, as the hand's winning status would be verified only to reveal an invalid hand.  Players may escape this dubious position, when another player wins the hand or has committed a chombo penalty.  An [[abortive draw]] may also prevent the chombo penalty, except suucha riichi.
 === Kan ===
 {{main|Kan#Kan during riichi}}
-Kan during riichi is a discretionary play.  Players must take not of the hand composition to determine, whether the kan is allowable or not.  Disallowable calls either alters the hand's waiting pattern or alters the hand's composition, where tile groupings are changed.  Improper calls are subject to chombo.
+Kan during riichi is a discretionary play. Players must take note of the hand composition to determine whether the kan is allowable or not. If the call alters the hand's waiting pattern or alters the hand's composition, kan is not allowed. Improper calls are subject to chombo if detected.
 === Furiten ===
 {{main|Furiten}}
-During riichi, a player may be furiten.  In this case, the riichi is considered to be a '''furiten riichi'''.  Likewise, after calling riichi, a player may decline the option to call on a winning tile, whether it be by self-draw or [[ron|by discard]].  However, if a win is declined, then the riichi declared hand is subject to furiten for the remainder of the hand.  Thus, all tiles discarded after the riichi declaration, as indicated by the discarded 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.
+During riichi, a player may be furiten.  In this case, the riichi is considered to be a '''furiten riichi'''.
-=== 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, he may flip the tiles underneath the [[dora]] and kan dora indicators. These flipped ''ura dora indicators'' may increase the value of his hand.
-=== Tochuu ryuukyoku ===
+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}}
-Tochuu ryuukyoku, or abortive draw, is in effect when suucha riichi occurs.  In this case, three riichis have been called; and a fourth one is called in place.  If the discarded tile is not claimed for a win, then the hand ends.
+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.
-=== Open riichi ===
+===Noten riichi===
-'''Open riichi''' {{kana|オープン立直}} is an [[optional yaku]], which is a modified version to riichi itself.  The principle works exactly in the same way as the original riichi.  However, there is an added bonus of 1-han attached, which is earned by revealing either the hand or the tile waits.  This naturally eases everyone else's ability to defend against the riichi.  In general, the intent involves winning by self-draw.  As a further optional rule, yakuman may be awarded if any player actually [[ron|plays into]] the open riichi.  This is more or less a harsh penalty for playing into a revealed hand.  Many official organizations and tournaments do not implement open riichi.  It is more or less reserved for casual or gambling game settings.
-=== Oikake riichi ===
+In real life play, a player may declare riichi without tenpai - this would be a '''noten riichi''' {{kana|ノテン立直}}, 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.
-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}}.  In English, this is often referred to as the "chase 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 ===
+== Scoring ==
-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 to cause players to defend.
-== Riichi based yaku ==
+Two yaku are specifically associated with riichi: '''ippatsu''' and '''double riichi'''. In addition, '''ura dora''' may be scored for any winning riichi hand.
-Two yaku are specifically associated with riichi: '''ippatsu''' and '''double riichi'''.
 === Ippatsu ===
 {{main|Ippatsu}}
-'''Ippatsu''' {{kana|一発}} is a separate yaku but is very dependent on riichi.  Riichi is required to score ippatsu, as the yaku is defined as a riichi winning before the declarer's next discard.  [[Naki|Tile calls]], including [[kan]], are able to nullify ippatsu by denying it.
+'''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.  Here, the player declares riichi on the first turn before one's own discard. No tile call may have interrupted the turn order before the declaration, where applicable.  For the [[dealer]], double riichi can never be interrupted.  As the name implies, this yaku is worth 2 han instead of 1 han, as a bonus for the initial timing.  With the added han value, a call for double riichi has a huge advantage over the other players in conjunction with the immediate speed and value compared to conventional riichi calls.
+'''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. 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 ==
@@ Line 84: / Line 89: @@
 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.
+=== Double riichi ===
+Double riichi has the same compatibility as riichi, except for [[chankan]]. This is because, for a regular hand, chankan may only be formed from an [[Kan#Shouminkan|added kan]], which itself requires a call for [[pon]] to happen first.
+* If the pon call happens before the riichi call, then double riichi is negated.
+* If the pon call happens after the riichi call, then the double riichi player must have declined their winning tile, invoking [[furiten]]. Chankan can only be won from [[ron]], so furiten prevents chankan entirely.
+An exception is the yakuman [[kokushi musou]]. Depending on [[Kokushi_musou#Chankan_rule_variation|rule variation]], kokushi may be won off a [[ankan|closed kan]], which does not require a previous pon call. Therefore, in order to win with double riichi + chankan, it must also have kokushi. Since this would be a yakuman hand, the yaku of "chankan" is never actually scored.
 == 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 depends 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]].
+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==

Riichi: Difference between revisions

Latest revision as of 21:00, 24 March 2024

Contents

Rules

Kan

Furiten

Suucha riichi

Noten riichi

Scoring

Ippatsu

Uradora

Double riichi

Open riichi

Compatibility

Double riichi

Strategy

Oikake riichi

Karaten riichi

External links

Navigation menu

	RCH	DRI	IPP	SMO	TAN	PFU	IPK	ITT	YAK	SDJ	SDO	TOI	SNA	SNK	CHA	JUN	RPK	SSG	HRO	HON	CHN	CHI	RIN	HAI	HOU	CHK
RCH
DRI

	RCH	DRI	IPP	SMO	TAN	PFU	IPK	ITT	YAK	SDJ	SDO	TOI	SNA	SNK	CHA	JUN	RPK	SSG	HRO	HON	CHN	CHI	RIN	HAI	HOU	CHK
RCH
DRI

	RCH	DRI	IPP	SMO	TAN	PFU	IPK	ITT	YAK	SDJ	SDO	TOI	SNA	SNK	CHA	JUN	RPK	SSG	HRO	HON	CHN	CHI	RIN	HAI	HOU	CHK
RCH
DRI