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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}}, meaning '''sacred discard''', is a particular rule associated with the tile discards. Basically, the player in [[Tenpai|tenpai]] is furiten if 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]].
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.
There are multiple ways for hand to enter furiten. The most common 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.  


Unlike many other mahjong variations, the [[discard pile]] for Japanese mahjong is specifically arranged in front of players.  The orderly discards help enforce the '''furiten rule''', by keeping track of discarded tiles.  [[naki|Tile calls]] have specific arrangements to point the source of these discarded tiles, so that they do not allow a loophole to furiten.  For every discard, the '''furiten rule''' applies when appropriate.
This rule is often used for [[defense]]: any tile a player discards is [[genbutsu|100% safe]] against that player.


== The rule ==
== Rule overview ==
Furiten imposes the following conditions:
[[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>]]
* '''Players in furiten may not win by ron''', under any circumstances.  
While in furiten, the hand is unable to call ron upon a discard. However, it can still win via self-draw, assuming the hand has valid yaku.
* Declaring ron while in furiten is penalized with a [[Chombo|chombo payment]].
* Players in furiten may still win by tsumo.


== Causes ==
A hand in [[tenpai]] is in furiten in any of the following scenarios:


When a player has called a win, via the call for ron, their hand should be checked for furiten. If the player is found to be furiten, then the win is invalid and the penalty for chombo is enforcedFor games played via the computer, players are usually denied the ability to declare ron in the first place.
* 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 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.


=== Discard-based furiten ===
A "winning tile" is a tile that could complete the "4 groups + 1 pair" winning shape, even if the hand couldn't actually win because it would lack yaku. (Tiles that could complete [[chiitoitsu|seven pairs]] or [[thirteen orphans]] also count.)
 
Note: If a hand is in furiten, it is unable to win off ''any'' player's discard, regardless of which tile caused the furiten. 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 pile
{{Discard pile
Line 27: Line 32:
}}
}}


A player is furiten if a winning tile is present in his own's [[discard pile]]. It does not matter whether this tile would have provided a yaku or not. Tiles turned sideways within open groups are considered part of the discarder's discard pile, hence the concern for indicating the tile source for open calls. As long as the player has not declared [[Riichi|riichi]], furiten can be avoided by altering the hand and changing [[Machi|tile waits]].
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).


'''Example tenpai hand'''
It is important to bear furiten in mind when developing a hand. Frequently, if a hand gets to tenpai and is furiten, it was inefficiently developed. This is not always the case, however, as a player can make a correct decision but still be in 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 in this instance.
"[[Atozuke]]" - or when a player is in tenpai, but has no guaranteed yaku - is a common reason for furiten. In these cases, the hand will only gain yaku if it draws a certain winning tile. If a different winning tile is drawn, the hand will have no yaku, and is thus forced to discard its own winning tile - entering furiten. This most commonly 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]].


=== Permanent furiten during riichi ===
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]].
{{main|Riichi}}


A riichi declarer may ignore a winning tile and not call ron. The ignored tile may have been a discarded tile or a [[Chankan|tile used to extend a minkou to a shominkan]] (kan called while having an open triplet).  After ignoring a winning tile, the riichi declarer is permanently furiten for the rest of the hand.  Therefore, it is advised for any player declaring riichi to call ron, at the first instance of a winning tile.  Otherwise, a win via [[mentsumo|tsumo]] becomes the only option.
'''Example tenpai hand'''
:{{machi
|pattern      = 77m34567p678s777z
|tilewaits    = 258p
}}


The furiten rule emphasizes that all tiles discarded by any player after the riichi declaration are deemed [[genbutsu|safe tiles]], along with the player's own discards. For this reason, the tile upon the riichi declaration is turned sideways to indicate the timing of the call.  Riichi declarers may not decline a ron against one player and expect to declare ron against another. Even if a winning tile different from the ignored one appears, the player may not call ron.
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.


=== Temporary furiten ===
=== 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.]]
[[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 winning tiles.  By declining a call for ron, the player then becomes temporarily furiten until the same player's next discard. In some plays, this may be a valid option in order to achieve a higher scoring hand or to target a specific player.


The furiten rule does not consider [[yaku]]. Sometimes, a hand can be completed with several tiles, but only some of them provide a yaku, others would produce a yakuless hand. If a yakuless tile appears, it must be ignored, because a winning hand must contain a yaku. The player must remain temporarily furiten until the next turn, even if a potential winning tile appears.
Calling a win is optional. If a player declines a call for ron, they enter furiten until their next turn (until their next discard, to be exact). Since it only lasts for one turn, it is called '''temporary furiten'''.
 
The main purpose of this rule is to prevent players from targeting other players. Once a player sees a tile discarded, they know that they can follow with the same tile and it will be safe from anyone that turn.
 
A player may deliberately skip a win, entering temporary furiten in the process. This is often done after [[situational analysis|point standing analysis]], such as:


This rule makes it harder to target a specific player with ron, or to ignore a winning tile of [[yasume|lesser value]] and hope for a more valuable tile. Sometimes, a player simply needs a specific win condition in order to attain a certain result, like [[Gyakuten|passing another player]]. Win conditions that do not meet certain expectations may end up being ignored.ile giving more value
*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]].  


Some rulesets may [[Rule variations#Furiten|vary the rules]] on temporary furiten with regards the timing of its cancellation, where a [[naki|tile call]] made by another player cancels the temporary furiten state. This is an uncommon variation, however.
Temporary furiten can also be entered by a player who does not have a guaranteed yaku, as described above. Otherwise, a player may mistakenly enter furiten if they don't know their waits correctly.
 
In a few [[Rule variations#Furiten|rulesets]], any tile call will cancel other players' temporary furiten.
 
=== 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}}
 
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 rule exists to prevent a riichi player from targeting others. With an open or [[dama]] hand, the hand ''could'' change waits on your next turn - this is why temporary furiten lasts until your next turn. A riichi hand cannot change waits, so permanent furiten lasts until the end of the hand. This also makes it easier to defend against a riichi. Any tile discarded after a riichi declaration is safe against that riichi player.
 
A player in riichi never has to worry about having no yaku unless they are playing with [[ryanhan shibari]]. When ryanhan shibari, a riichi without a guaranteed second yaku may be quite dangerous due to furiten.


== Strategy ==
== Strategy ==


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


{{main|Defense}}
The furiten rule is essential for defensive play. 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 00:03, 22 October 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.

There are multiple ways for hand to enter furiten. The most common 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 in furiten, the hand is unable to call ron upon a discard. However, it can still win via self-draw, assuming 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 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 a tile that could complete the "4 groups + 1 pair" winning shape, even if the hand couldn't actually win because it would lack yaku. (Tiles that could complete seven pairs or thirteen orphans also count.)

Note: If a hand is in furiten, it is unable to win off any player's discard, regardless of which tile caused the furiten. 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

Example discard pile



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

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. Frequently, if a hand gets to tenpai and is furiten, it was inefficiently developed. This is not always the case, however, as a player can make a correct decision but still be in furiten.

"Atozuke" - or when a player is in tenpai, but has no guaranteed yaku - is a common reason for furiten. In these cases, the hand will only gain yaku if it draws a certain winning tile. If a different winning tile is drawn, the hand will have no yaku, and is thus forced to discard its own winning tile - entering furiten. This most commonly 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.

Finally, a player considering a 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 [passed] on a tenhou or chiihou tsumo.

Example tenpai 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.

Temporary furiten

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

Calling a win is optional. If a player declines a call for ron, they enter furiten until their next turn (until their next discard, to be exact). Since it only lasts for one turn, it is called temporary furiten.

The main purpose of this rule is to prevent players from targeting other players. Once a player sees a tile discarded, they know that they can follow with the same tile and it will be safe from anyone that turn.

A player may deliberately skip a win, entering temporary furiten in the process. This is often 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.

Temporary furiten can also be entered by a player who does not have a guaranteed yaku, as described above. Otherwise, a player may mistakenly enter furiten if they don't know their waits correctly.

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.

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 rule exists to prevent a riichi player from targeting others. With an open or dama hand, the hand could change waits on your next turn - this is why temporary furiten lasts until your next turn. A riichi hand cannot change waits, so permanent furiten lasts until the end of the hand. This also makes it easier to defend against a riichi. Any tile discarded after a riichi declaration is safe against that riichi player.

A player in riichi never has to worry about having no yaku unless they are playing with ryanhan shibari. When ryanhan shibari, a riichi without a guaranteed second yaku may be quite dangerous due to furiten.

Strategy

Defense

The furiten rule is essential for defensive play. 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