View source for Furiten

[[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.]]
While a player's hand is in '''furiten''' {{kana|振聴 or 振り聴 or フリテン}},{{note|Furiten {{kana|振聴}} means "swung [[tenpai]]". Here "swinging" refers to the motion of discarding a tile, so it may be more freely translated as "discarded tenpai".}} 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.

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 [[genbutsu|100% safe]] against that player.

== 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>]]

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 [[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.

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 ===
[[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.]]

Calling a win is optional. If a non-[[riichi]] player does not ron a "winning tile" (even if a win cannot be declared 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 [[situational analysis|point standing analysis]], such as:

*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]]. 

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 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 [[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.

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. For example, say Opponent A is in open tenpai. Opponent B discards 5-sou. making it safe for a turn. Opponent A could change waits to 5-sou, so even if temporary furiten lasted permanently, the 5-sou would not be safe. But, since riichi forbids changing waits, permanent furiten lasts until the end of the hand.

== 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
}}

:{{machi
|pattern      = 77m34567p678s777z
|tilewaits    = 258p
}}

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|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.

[[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, players may need to enter a furiten tenpai:
* The best [[tile efficiency]] discards can occasionally cause furiten (e.g., discard a lone 1-sou, draw a 3-sou then 2-sou.).
* When defending and developing the hand simultaneously, a furiten tenpai might occur.
* Rarely, a [[dama]] hand can intentionally choose to 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 is generally done to score a yaku like [[pinfu]] or [[sanshoku]] if the [[situational analysis|point situation]] demands a higher value hand.

An important thing to realize is that you only enter furiten when in tenpai. Therefore, it is not bad to keep a wait that could cause furiten later. So long as the wait is completed 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. When declaring [[riichi]], a [[ryanmen]] furiten is about equal to a 1-sided regular wait; the ryanmen furiten is a bit less likely to win, but scores more due to guaranteed [[menzen tsumo]].

===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:

:{{#mjt:22288m23p3456'78s}} Draw: {{#mjt:3p}} Waiting for: {{#mjt:14p}} (furiten)

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.

== Notes ==
{{notes}}

== References ==
{{references}}

== External links ==
{{jpwiki|振聴}}

[[Category:Terminology]]
[[Category:Game rules]]
[[Category:Strategy]]