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[[Image:Furiten.png|right|thumb|250px|[http://tenhou.net/0/?log=2012110112gm-0009-7447-14ec5c8d&tw=0&ts=4 Baiman tenpai], in furiten due to 9-sou in discard.  Ron cannot be called here.]]
[[Image:Furiten.png|right|thumb|250px|[http://tenhou.net/0/?log=2012110112gm-0009-7447-14ec5c8d&tw=0&ts=4 Baiman tenpai], in furiten due to 9-sou in discard.  Ron cannot be called here.]]
'''Furiten''' {{kana|振聴}} is a game status where a player cannot declare [[ron]] because of a decision not to use a winning tile. A player in [[Tenpai|tenpai]] is furiten if any of that player's winning tiles are present in one's own discard pile or, in certain conditions, another player's discard pile or [[shouminkan]]. Players in furiten may still win by [[tsumo]], but not by ron.  A call of ron while furiten is penalized by [[chombo]], although computer games will generally forbid the player from declaring a furiten ron.
While a player's hand is in '''furiten''' {{kana|振聴}}, they cannot declare a win on another player's [[ron|discard]] (i.e., they cannot [[ron]]). They are still allowed to win with their own draw ([[tsumo]]), assuming the hand is valid.


In all cases, the furiten rule requires a player to be aware of all of their [[machi|tile waits]]. If a player is [[tenpai]] but does not realize all of their possible waits, they may not be aware that they are furiten and, as a result, call an illegal win. This is especially true of a player who has called [[riichi]], because they can be furiten off of anyone's discard for a long period of time.
The most common way to enter furiten is from discards: if a player had previously discarded a tile that their hand could now win with, their hand is considered furiten. Furiten is also caused when a player skips a win.


To enforce furiten, the [[discard pile]] is specifically arranged in front of players and [[Naki|tile calls]] have one tile turned to indicate who discarded the tile. The discard arrangements allow players to keep track of who discarded which tiles.  During a hand, players should take note of their status in relation to furiten and avoid calling winning hands while in furiten.  Likewise, any calls for winning hands should have the discards checked for furiten.  Any game involving software already checks for furiten, alerts players, and denies winning calls.
This rule is often used for [[defense]]: any tile a player discards is [[genbutsu|100% safe]] against that player.


Furiten is translated as '''sacred discard''' in Chinese. In consequence, English terminology had made this the equivalent. However, this translation bears no relation to the Japanese term ({{kana|振り聴牌}}: thrown-away tenpai).
== Rule overview ==
[[Image:Furiten ron MLeague.png|right|250px|thumb|Furiten ron with a 5-sided wait in [[M.League]] invoking [[chombo]].<ref>[https://www.youtube.com/watch?v=RQ102K4Kl8w&t=260 Furiten-ron chombo] (M.League 24-25, Sep.27 #2, South 2 Round 1 honba, North seat)</ref>]]


== Rule statement ==
While the hand is in furiten, the player is unable to call ron off any tile, but they can win by [[tsumo]] ''if'' the hand has valid [[yaku]].


A player in tenpai is in furiten in any of the following scenarios:
A hand in [[tenpai]] is in furiten in any of the following scenarios:
* When at least one of the hand's current winning tiles have been discarded by you before, the hand enters furiten.
** A tile does not have to be physically in your discard pile to invoke furiten. If an opponent [[naki|called]] on your discarded tile, said tile will still trigger furiten.
* After declaring [[riichi]], if the first winning tile is skipped, the hand permanently enters furiten. 
* When not in riichi, when a winning tile is skipped, the hand enters temporary furiten. This furiten lasts until the player's next discard.


* They have discarded, at any point in the hand, one of their winning tiles.
A "winning tile" is any tile that could complete a "4 groups + 1 pair" winning shape (or [[chiitoitsu]] / [[kokushi musou]]), ''even if the hand could not actually win because it would lack yaku''.
* They are not in [[riichi]]; since their last turn, another player either discarded or made a [[shouminkan]] of one of their winning tiles; and they did not call ron on that tile.
* They are in riichi; since they declared riichi, another player either discarded or made a [[shouminkan]] of one of their winning tiles; and they did not call ron on that tile.


When evaluating furiten, [[yaku]] are not taken into account. A player may find themselves in a situation where they are forced to discard or pass on a tile that does not give them a yaku, but would otherwise have completed their hand. This will lead to furiten.
Note that, when in furiten, the hand is unable to win off ''any'' discard; the tile that "caused" furiten is irrelevant. For example, if your hand is waiting to win with 2p and 5p, and you had discarded 2p before, you are unable to win off an opponent's 5p.


A player who is in furiten cannot call ron, although they can still call tsumo or make any other legal play.
=== Discard furiten ===
Discard furiten, the most common form of furiten, occurs when a player's own winning tile has been discarded before. A hand can escape this type of furiten by changing its waits.


=== Own discard furiten ===
Because discard furiten exists, any tile a player has discarded is 100% safe against that player. Even if the player is waiting on that tile, they cannot ron (as they'd be in furiten).


{{Discard pile
It is important to bear furiten in mind when developing a hand. If a hand gets to tenpai and is furiten, it may have been inefficiently developed. This is not always the case, however, as a player can make a correct decision but still be in furiten.
|align    = right
|title    = Example discard pile
|tilerow1 = 1s6527z7s
|tilerow2 = 23p3s6z4s1m
|tilerow3 = 4z
|source  = 2-pin in this discard applies furiten to the example hand
}}


When a player is in furiten because of their own discard, it is sometimes called '''permanent furiten'''. This name is slightly misleading because a player can (unless they have declared riichi) change their waits to avoid this form of furiten.
A hand with no guaranteed yaku - a state known as [[atozuke]] - is particularly susceptible to furiten. When a hand is in atozuke, only some winning tiles would result in having a yaku. If a non-yaku winning tile is obtained, the hand is unable to win, and forced to enter discard furiten. Atozuke often occurs with:
*A [[shanpon]] wait, with one tile completing a [[yakuhai]] triplet, and the other having no yaku.
*A [[ryanmen]] wait on 14 or 69 on a hand that would otherwise complete [[tanyao]].


All of a player's discards can be checked at any time during play, by looking at their discard pools and the rotated tiles in other players' tile calls. This leads to the most basic strategy to avoid dealing into a player's hand: tiles they have already discarded are guaranteed safe against a ron call from that player.
=== Temporary furiten ===
[[Image:TempFuriten.png|thumb|right|250px|Ron declined, so [http://tenhou.net/0/?log=2014022617gm-0089-0000-ee8c6631&tw=2&ts=11 temporary furiten invoked] until the next own's tile draw.]]


During hand development, it is important to bear furiten in mind. Most of the time, if a hand gets to tenpai and is furiten at that point, it indicates that the hand was inefficiently developed. This is not always the case, as sometimes a player makes a tactically correct decision and finds themselves in furiten anyway.
Calling a win is optional. If a non-[[riichi]] player does not ron a "winning tile" (even if said tile can't win due to lack of yaku), they enter temporary furiten until their next discard. Since it lasts for 1 turn, it is called temporary furiten.


The most common reason for furiten, however, is when a player is already tenpai with an open hand, and does not have a guaranteed yaku. While they may have a winning tile that provides them with a yaku, if that draw another tile which completes the hand without a yaku, then they will be forced into furiten on the next discard. This most commonly occurs with a [[shanpon]] wait, one pair of which would give [[yakuhai]], or with a [[ryanmen]] wait on 14 or 69 on a hand that would otherwise complete [[tanyao]].
Sometimes, a player may misinterpret their waits, entering furiten in the process. Alternatively, a player may be in atozuke and a non-yaku giving tile is discarded. Otherwise, a player may intentionally skip a win, entering temporary furiten in the process. This is mainly done after [[situational analysis|point standing analysis]], such as:


Finally, a player considering a [[daburu riichi|double riichi]] should carefully inspect their hand before discarding; if they had a complete hand to begin with, then being in furiten will add insult to the injury of having [[http://osamuko.com/delicious-riichi-button-must-click-it/ passed]] on a [[tenhou and chiihou|tenhou or chiihou tsumo]].
*When a player is close to [[tobi|bankrupting]], a player in 1st may want to target them in order to end the game faster.
*When close to [[oorasu|all last]], a player may need to ron a specific player to [[gyakuten|rise up in rank]].  


'''Example tenpai hand'''
In a few [[Rule variations#Furiten|rulesets]], any tile call will cancel other players' temporary furiten.
:{{#mjt:77m 34567p 678s 777z}}, waiting on {{#mjt:2p}}, {{#mjt:5p}}, or {{#mjt:8p}}


This hand waits on three different tiles. If the player has a 2-pin their discard pile, then the hand is in furiten and may not win by ron on any tile. Even if a 5-pin or 8-pin gets discarded by an opponent, ron may not be called.
=== Permanent furiten during riichi ===
[[Image:Furiten riichi.png|250px|thumb|right|[http://tenhou.net/0/?log=2015082022gm-0089-0000-a1177c83&tw=1&ts=11 Furiten riichi] applied upon declaration and discard declining a winning hand.]]
{{main|Riichi}}


=== Temporary furiten ===
When a player has declared riichi, the state of temporary furiten does not expire. Therefore, if a riichi hand skips a win, it is no longer able to call ron. This is known as permanent furiten, or riichi furiten.  
[[Image:TempFuriten.png|thumb|right|250px|Ron declined, so [http://tenhou.net/0/?log=2014022617gm-0089-0000-ee8c6631&tw=2&ts=11 temporary furiten invoked] until the next own's tile draw.]]
Any player in tenpai has the option to ignore a winning tile.  By declining a call for ron, the player then becomes temporarily furiten until their next discard. This is called '''temporary furiten''', as it expires shortly after it occurs. Although most of the time, it will apply to a discarded tile, it can also apply to a tile used to create a [[shouminkan]]. Temporary furiten cannot apply to a tile used to create an [[ankan]], as if a player can call ron on an ankan, then they have a single-sided [[kokushi musou]] wait (and even then, this is not permitted in [[Rule variations#Kokushi and chankan|all rulesets]]). If they decline a ron, then their hand is dead and cannot be completed.


The primary purpose of the rule is to prevent a player from targeting a later player in the turn order. Once a player sees a tile discarded, they know that they can follow with the same tile and it will be safe.
Since riichi is a yaku, there is no need to worry about a lack of yaku, unless under [[ryanhan shibari]].


While this is often a mistake to enter temporary furiten, done by a player who does not know their waits correctly or is not paying attention, it may be done deliberately in order to achieve a higher scoring hand or to target a specific player. This becomes much more common in [[orasu]], where a player may gain little benefit from winning a hand that does not [[gyakuten|let them pass another player]]. Temporary furiten can also be entered by a player who does not have a guaranteed yaku, as described above. This is much less devastating than drawing the [[yasume]] tile, however, because it is only temporary.
== Reasoning ==
Furiten exists for two main reasons:


Uncommonly, some rulesets [[Rule variations#Furiten|vary the rules]] by allowing a tile call made by another player to cancel temporary furiten. This variation is considered by many to be a poor one.
1. It helps players [[defense|defend]] against other player's hands:
* Discard furiten: Any tile a player has discarded before is 100% safe against that player.
* Temporary furiten: The tile the player on your left discards is 100% against all players that turn. The tile the player across from you discards is 100% safe against the rightmost player.
* Permanent furiten: After a player declares riichi, any tile anyone discards is safe against that riichi player.


=== Permanent furiten during riichi ===
2. It makes it much harder to target other players.
[[Image:Furiten riichi.png|250px|thumb|right|[http://tenhou.net/0/?log=2015082022gm-0089-0000-a1177c83&tw=1&ts=11 Furiten riichi] applied upon declaration and discard declining a winning hand.]]
* Because discard furiten exists, players cannot skip a tsumo win in order to ron another player.
{{main|Riichi}}
* Because temporary and permanent furiten exist, players must take the first ron or enter some form of furiten. Since a non-riichi hand ''could'' change its waits every turn, temporary furiten only lasts 1 turn. Because a riichi hand cannot change its waits, permanent furiten lasts until the end of the hand.


When a player has declared riichi, the state of temporary furiten does not expire for them. This means that they only have one opportunity to call ron; if they pass on it, then they can thereafter only win by tsumo. This rule is a critical part of defense against riichi, as it means that any tiles discarded since the declaration is safe.
== Example ==
{{Discard pile
|align    = right
|title    = Example discard pile
|tilerow1 = 1s6527z7s
|tilerow2 = 23p3s6z4s1m
|tilerow3 = 4z
|source  = 2-pin in this discard applies furiten to the example hand
}}


The rule for riichi can be understood as saying that temporary furiten expires the next time the player has an opportunity to change their hand. Because a player in riichi cannot change their hand, their temporary furiten never expires.
:{{machi
|pattern      = 77m34567p678s777z
|tilewaits    = 258p
}}


A player in riichi never has to worry about [[yasume]] putting them in furiten unless they are playing with [[ryanhan shibari]]. When ryanhan shibari, a riichi without a guaranteed second yaku may be quite dangerous due to furiten.
This hand waits on three different tiles. If the player has a 2-pin in their discard pile, then the hand is in furiten and may not win by ron on any tile. Even if a 5-pin or 8-pin gets discarded by an opponent, ron may not be called.


== Strategy ==
== Strategy ==


=== Defense ===
=== Defense ===
{{main|Defense}}


{{main|Defense}}
The furiten rule is essential for defensive play. As mentioned in the [[#Reasoning|Reasoning]] section, any tile that would invoke furiten to a player is 100% safe against that player:
*Discard furiten: Any tile that an opponent discarded is 100% against them.
*Permanent furiten: After an opponent declares [[riichi]], any tile anyone discards is 100% safe against that riichi player.
*Temporary furiten: Any tile that the player to your left has discarded this turn is 100% safe against every player for this turn only.


The furiten rule may be applied for defensive play, which focuses on discarding [[safe tiles]]. By discarding tiles that are also visible in an opponent's discard pile, a player can avoid a ron call by that opponent.  Likewise, usage of [[suji]] and [[kabe]] may also help players deduce safe tiles, based on opponent discard.  This is applied when a player does not have any matching tiles in the hand with opponent discard; or a player may rather keep certain tiles, for the sake of developing the hand without [[betaori|tearing it apart]].
[[Suji]] is a technique that is related to furiten. When a tile is suji, a hand cannot have a [[ryanmen]] wait (2-sided wait; the most common type of wait) for that tile without being in furiten.


===Working with furiten===
===Working with furiten===
Sometimes, it may be necessary to enter tenpai when it would be furiten. Often, this is the result of developing the hand and defending simultaneously.
An important thing to realize is that you only enter furiten when in tenpai. Therefore, it is not the worst thing to keep a wait that could cause furiten later. So long as you complete the wait before tenpai, there is no punishment.
Even if you do enter furiten, a 3-sided wait in furiten is still strong, and a 2-sided wait in furiten remains reasonable (around the level of a 1-sided wait).
Rarely, a hand in [[damaten]] can intentionally enter furiten. In this case, the hand is in tenpai, but after a winning tile is drawn, the player declares riichi instead of a win - immediately entering furiten. This may be done to score a yaku like [[pinfu]] or [[sanshoku]].
===Exiting furiten===
To exit discard furiten, you can change the hand's [[wait]] so that it can no longer win off any of the discarded tiles. For example:


Sometimes, it may be necessary to deliberately place the hand in furiten.  Often, this is the result of developing the hand and defending simultaneously.  To escape the bind applied by furiten, then the hand's [[machi|tile wait(s)]] must simply change by adjusting and changing the tiles in the hand with subsequent tile draws.  Of course, a player may place greater expectation on tsumo to win rather than ron.
:{{#mjt:22288m23p3456'78s}} Draw: {{#mjt:3p}} Waiting for: {{#mjt:14p}} (furiten)


=== Furiten tsumo ===
If the hand had discarded {{#mjt:1p}} previously, it would be in furiten. By drawing {{#mjt:3p}} and discarding {{#mjt:2p}}, it now waits on {{#mjt:3p}} and {{#mjt:8m}}. Thus, the hand is no longer waiting on {{#mjt:1p}}, and is no longer in furiten.


Hands in furiten can still win, as furiten imposes a limit of tsumo only.  For open hands, the hand requires a valid yaku.  For closed hands, [[mentsumo]] will be acceptable or added.
== References ==
<references/>


== External links ==
== External links ==

Latest revision as of 07:25, 20 November 2024

Baiman tenpai, in furiten due to 9-sou in discard. Ron cannot be called here.

While a player's hand is in furiten 「振聴」, they cannot declare a win on another player's discard (i.e., they cannot ron). They are still allowed to win with their own draw (tsumo), assuming the hand is valid.

The most common way to enter furiten is from discards: if a player had previously discarded a tile that their hand could now win with, their hand is considered furiten. Furiten is also caused when a player skips a win.

This rule is often used for defense: any tile a player discards is 100% safe against that player.

Rule overview

Furiten ron with a 5-sided wait in M.League invoking chombo.[1]

While the hand is in furiten, the player is unable to call ron off any tile, but they can win by tsumo if the hand has valid yaku.

A hand in tenpai is in furiten in any of the following scenarios:

  • When at least one of the hand's current winning tiles have been discarded by you before, the hand enters furiten.
    • A tile does not have to be physically in your discard pile to invoke furiten. If an opponent called on your discarded tile, said tile will still trigger furiten.
  • After declaring riichi, if the first winning tile is skipped, the hand permanently enters furiten.
  • When not in riichi, when a winning tile is skipped, the hand enters temporary furiten. This furiten lasts until the player's next discard.

A "winning tile" is any tile that could complete a "4 groups + 1 pair" winning shape (or chiitoitsu / kokushi musou), even if the hand could not actually win because it would lack yaku.

Note that, when in furiten, the hand is unable to win off any discard; the tile that "caused" furiten is irrelevant. For example, if your hand is waiting to win with 2p and 5p, and you had discarded 2p before, you are unable to win off an opponent's 5p.

Discard furiten

Discard furiten, the most common form of furiten, occurs when a player's own winning tile has been discarded before. A hand can escape this type of furiten by changing its waits.

Because discard furiten exists, any tile a player has discarded is 100% safe against that player. Even if the player is waiting on that tile, they cannot ron (as they'd be in furiten).

It is important to bear furiten in mind when developing a hand. If a hand gets to tenpai and is furiten, it may have been inefficiently developed. This is not always the case, however, as a player can make a correct decision but still be in furiten.

A hand with no guaranteed yaku - a state known as atozuke - is particularly susceptible to furiten. When a hand is in atozuke, only some winning tiles would result in having a yaku. If a non-yaku winning tile is obtained, the hand is unable to win, and forced to enter discard furiten. Atozuke often occurs with:

  • A shanpon wait, with one tile completing a yakuhai triplet, and the other having no yaku.
  • A ryanmen wait on 14 or 69 on a hand that would otherwise complete tanyao.

Temporary furiten

Ron declined, so temporary furiten invoked until the next own's tile draw.

Calling a win is optional. If a non-riichi player does not ron a "winning tile" (even if said tile can't win due to lack of yaku), they enter temporary furiten until their next discard. Since it lasts for 1 turn, it is called temporary furiten.

Sometimes, a player may misinterpret their waits, entering furiten in the process. Alternatively, a player may be in atozuke and a non-yaku giving tile is discarded. Otherwise, a player may intentionally skip a win, entering temporary furiten in the process. This is mainly done after point standing analysis, such as:

  • When a player is close to bankrupting, a player in 1st may want to target them in order to end the game faster.
  • When close to all last, a player may need to ron a specific player to rise up in rank.

In a few rulesets, any tile call will cancel other players' temporary furiten.

Permanent furiten during riichi

Furiten riichi applied upon declaration and discard declining a winning hand.
Main article: Riichi

When a player has declared riichi, the state of temporary furiten does not expire. Therefore, if a riichi hand skips a win, it is no longer able to call ron. This is known as permanent furiten, or riichi furiten.

Since riichi is a yaku, there is no need to worry about a lack of yaku, unless under ryanhan shibari.

Reasoning

Furiten exists for two main reasons:

1. It helps players defend against other player's hands:

  • Discard furiten: Any tile a player has discarded before is 100% safe against that player.
  • Temporary furiten: The tile the player on your left discards is 100% against all players that turn. The tile the player across from you discards is 100% safe against the rightmost player.
  • Permanent furiten: After a player declares riichi, any tile anyone discards is safe against that riichi player.

2. It makes it much harder to target other players.

  • Because discard furiten exists, players cannot skip a tsumo win in order to ron another player.
  • Because temporary and permanent furiten exist, players must take the first ron or enter some form of furiten. Since a non-riichi hand could change its waits every turn, temporary furiten only lasts 1 turn. Because a riichi hand cannot change its waits, permanent furiten lasts until the end of the hand.

Example

Example discard pile



2-pin in this discard applies furiten to the example hand

Waiting for:

This hand waits on three different tiles. If the player has a 2-pin in their discard pile, then the hand is in furiten and may not win by ron on any tile. Even if a 5-pin or 8-pin gets discarded by an opponent, ron may not be called.

Strategy

Defense

Main article: Defense

The furiten rule is essential for defensive play. As mentioned in the Reasoning section, any tile that would invoke furiten to a player is 100% safe against that player:

  • Discard furiten: Any tile that an opponent discarded is 100% against them.
  • Permanent furiten: After an opponent declares riichi, any tile anyone discards is 100% safe against that riichi player.
  • Temporary furiten: Any tile that the player to your left has discarded this turn is 100% safe against every player for this turn only.

Suji is a technique that is related to furiten. When a tile is suji, a hand cannot have a ryanmen wait (2-sided wait; the most common type of wait) for that tile without being in furiten.

Working with furiten

Sometimes, it may be necessary to enter tenpai when it would be furiten. Often, this is the result of developing the hand and defending simultaneously.

An important thing to realize is that you only enter furiten when in tenpai. Therefore, it is not the worst thing to keep a wait that could cause furiten later. So long as you complete the wait before tenpai, there is no punishment.

Even if you do enter furiten, a 3-sided wait in furiten is still strong, and a 2-sided wait in furiten remains reasonable (around the level of a 1-sided wait).

Rarely, a hand in damaten can intentionally enter furiten. In this case, the hand is in tenpai, but after a winning tile is drawn, the player declares riichi instead of a win - immediately entering furiten. This may be done to score a yaku like pinfu or sanshoku.

Exiting furiten

To exit discard furiten, you can change the hand's wait so that it can no longer win off any of the discarded tiles. For example:

Draw: Waiting for: (furiten)

If the hand had discarded previously, it would be in furiten. By drawing and discarding , it now waits on and . Thus, the hand is no longer waiting on , and is no longer in furiten.

References

  1. ↑ Furiten-ron chombo (M.League 24-25, Sep.27 #2, South 2 Round 1 honba, North seat)

External links

Furiten in Japanese Wikipedia
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