Kan strategy: Difference between revisions

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The mechanics of calling for [[kan]] requires some assessment, as risks are involved. In plenty of cases, a kan is a risky move, even though there are potential benefits.
[[Kan]] is a naturally risky action, due to the nature of [[kandora]]. When a player calls kan, any player - including the kan-declarer's opponents - may benefit from the kandora. Therefore, some assessment should be made when calling kan.


== Offense ==
== Offense ==
Under most circumstances, the call for kan is an offensive move.  The player gets an extra draw from the [[rinshanpai]] and chances for the kandora.  If the hand is tenpai, then the hand has a chance for [[rinshan kaihou]].
Under most circumstances, the call for kan is an offensive move.  The player gets an extra draw from the [[rinshanpai]] and chances for the kandora.  If the hand is tenpai, then the hand has a chance for [[rinshan kaihou]].


== Defense ==
If a kan-declaring player wins, then their opponents will never get a chance to benefit from kan dora. Therefore, if a player believes that they are likely to win (e.g. reaching [[tenpai]] early, or [[iishanten]] very early), then kan may be advised.
A safe place for dangerous tiles is in one's own hand.  A call for ankan ensures for all four of a single tile type to remain in the hand. Furthermore, it may be possible to apply [[kabe]] making appropriate tiles look safer.  For the other kan types, the hand is already open.  In the case for daiminkan, the hand is either already open or about to be opened.  If the tile to be called is already a safe tile, then it may be a better idea to not call, as three safe tiles are already in possession.  For shouminkan or kakan, the added risk of chankan is applied.


=== Declining ===
=== Riichi ===
An interesting consideration is to decline kan.  This may be possible in one of two ways: Discarding the fourth tile, or simply holding on to it.  Doing so prevents additional dora indicators, which could be favorable to opponents.  The tile itself may be dangerous.  If the hand is undergoing betaori, then there is no interest for kan in the first place.
{{main|Riichi|Kan#Restrictions}}


== Tile efficiency ==
A call for kan reveals kan dora. Any player who has declared riichi will also benefit from kan ura dora. Therefore, a player in riichi will often call kan if it is possible. First, it reveals two extra dora instead of the usual one. Second, a player in riichi is already in tenpai; thus, they are more likely to win. Conversely, opponents should be wary about calling kan when another player is in riichi for the same reasons.
{{main|Tile efficiency}}


=== Call timing ===
When playing with real tiles, players must always be aware of whether a kan call can [[Kan#Restrictions|legally be called]]. Players using game software or online platforms do not need to be aware because the programs handle the situations for them.
A player may have a hand warranting for kan. Given that the play is discretionary, it may not be necessary to call kan immediately.  Though, the delay of the call may actually affect tile efficiency if the extra tile is not connected to another tile in the hand.


== Kandora ==
== Defense ==
{{main|Kandora}}
A player in betaori (full folding) should usually avoid declaring kan, because it removes four discard options from your hand, and may increase the opponent's score. For shouminkan/kakan, there is an added risk of [[chankan]].


Extra dora indicators are shown due to calls for kan. This is the '''kandora'''. While a player may chance to receive extra dora, an equal chance applies to grant other players the extra dora. With that said, extra consideration must be taken when given the opportunity to call kan.
Players can apply [[kabe]] if an opponent calls kan. If all four tiles are visible, e.g. from an opponent's kan call, then it will make certain types of wait impossible. For example, If a kan of 3 is called, then the wait patterns of 23, 34, and 13 of the same suit are impossible. Thus, 1 and 4 become safer. If all four tiles are in your own hand, then there's no need to actually call kan in order to benefit from kabe.


== Shifting the haiteipai ==
=== Shifting the draw ===
When kan is called, one tile from the live wall shifts over to the dead wall.  With this mechanic, players can actually call kan to deny players a draw, and more specifically, it is the haitei draw.
When kan is called, one tile from the live wall shifts over to the dead wall.  With this mechanic, players can call kan to deny players [[ippatsu]] or the [[haitei]] draw.


== Riichi ==
== Call timing ==
{{main|Riichi|Kan#Restrictions}}
{{main|Tile efficiency}}
 
Kan during riichi has to be discrete because of a few considerations.  Like all things mahjong, the pros and cons must be weighed before making a decision.  This is especially true with kan calls. 
 
First of all, calls for kan reveal extra kan dora.  If a player in riichi has the opportunity to make a kan call, usually the call is made for the added chance for kan dora and ura dora.  Players facing a riichi may make the alternative consideration.  The added chance for kan dora and ura dora may enhance an opponent's hand.


Second of all, players must always be aware whether a kan call can [[Kan#Restrictions|legally be called]].  Players using game software or online platforms do not need to be aware because the programs handle the situations for them. With real tiles, the kan validity must be made.
Kan is not mandatory, so players do not have to call kan immediately. Instead, they can keep the fourth tile in their hand, declaring kan if/when appropriate. However, delaying a kan will reduce tile efficiency, if the extra tile is not connected to another tile in the hand.


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

Revision as of 21:48, 17 March 2024

Kan is a naturally risky action, due to the nature of kandora. When a player calls kan, any player - including the kan-declarer's opponents - may benefit from the kandora. Therefore, some assessment should be made when calling kan.

Offense

Under most circumstances, the call for kan is an offensive move. The player gets an extra draw from the rinshanpai and chances for the kandora. If the hand is tenpai, then the hand has a chance for rinshan kaihou.

If a kan-declaring player wins, then their opponents will never get a chance to benefit from kan dora. Therefore, if a player believes that they are likely to win (e.g. reaching tenpai early, or iishanten very early), then kan may be advised.

Riichi

A call for kan reveals kan dora. Any player who has declared riichi will also benefit from kan ura dora. Therefore, a player in riichi will often call kan if it is possible. First, it reveals two extra dora instead of the usual one. Second, a player in riichi is already in tenpai; thus, they are more likely to win. Conversely, opponents should be wary about calling kan when another player is in riichi for the same reasons.

When playing with real tiles, players must always be aware of whether a kan call can legally be called. Players using game software or online platforms do not need to be aware because the programs handle the situations for them.

Defense

A player in betaori (full folding) should usually avoid declaring kan, because it removes four discard options from your hand, and may increase the opponent's score. For shouminkan/kakan, there is an added risk of chankan.

Players can apply kabe if an opponent calls kan. If all four tiles are visible, e.g. from an opponent's kan call, then it will make certain types of wait impossible. For example, If a kan of 3 is called, then the wait patterns of 23, 34, and 13 of the same suit are impossible. Thus, 1 and 4 become safer. If all four tiles are in your own hand, then there's no need to actually call kan in order to benefit from kabe.

Shifting the draw

When kan is called, one tile from the live wall shifts over to the dead wall. With this mechanic, players can call kan to deny players ippatsu or the haitei draw.

Call timing

Kan is not mandatory, so players do not have to call kan immediately. Instead, they can keep the fourth tile in their hand, declaring kan if/when appropriate. However, delaying a kan will reduce tile efficiency, if the extra tile is not connected to another tile in the hand.

External links