Kan: Difference between revisions

'''Kan''' {{kana|カン}} is a special [[naki|tile call]] in the game. This call forms a [[mentsu|tile grouping]] of four identical tiles, called '''kantsu''' {{kana|槓子}}. Just like all tile calls, the call itself is optional; thus, an opportunity to call kan is not mandatory.

While appearing as a four-of-a-kind, the tiles used to form kantsu actually function as a [[koutsu|three-of-a-kind]] plus one extra tile. With that in mind, tiles called for kan still interpreted as "triplets" particularly for [[Yaku#Triplet|triplet-based yaku]], such as [[toitoi]] and [[sanankou]]. For every kan declaration, players are required to take an extra tile draw from the [[dead wall]]. This drawn tile is called the '''[[rinshanpai]]''', or '''dead wall draw'''.  After the kan call and player's discard, then another [[dora|dora indicator]] is revealed.

The call for kan is a discretionary play, with its own set of rules and restrictions.  Under all circumstances, a player may call kan or decline when given the opportunity.  The strength of kan play stems from the exclusive access to the dead wall and the revealing of additional dora.  At the same time, kan play is very risky, where other players may end up as the benefactors. Therefore, players may decline calling the kan to minimize risk.  Choosing to do so or not, this play does require some assessment; and players are not encouraged to make such calls recklessly.  On the other hand, players may rely on kans, when it is needed.

Like the other tile calls, kan is also a tile call. However, it comes with special properties and rules. These rules apply when a player possesses or gains possession of four of the same tile; and then the player makes the kan call.

# The four identical tiles are shown and are set aside, like an open call. Together, the four tiles now count as one [[Mentsu|tile group]].

A special case may involve the yaku, [[chankan]]. If the kan call involves a shouminkan and the added tile is a winning tile for another player, then chankan may be applied upon the declaration of another player's winning hand. In this case, the hand ends before the player even gets to draw the extra tile from the dead wall. Thus, the process of calling kan gets interrupted in favor of another player's winning hand.

The call for kan reveals additional dora in the form of [[dora|kandora]]. The timing of this reveal is variable, depending on [[Dora variations|the rule set and/or game platform]].  The simplest rule invokes an immediate reveal upon the declaration; and so, this rule would immediately place the kan reveal after step 1. Others distinguish the timing between open and closed kans. Here, closed kans would be granted an immediate reveal; however, open kans would produce another kandora indicator after a discard or another kan (i.e. after either step 6 or 7). Regarding the timing of the kandora, players will need to consult organizational, tournament, and/or local rules.

*Closed triplet with the fourth tile type discarded

*Open triplet with the fourth tile type drawn

*All four tile types drawn

In this example, kan may be called twice in a row after drawing '''1-man'''.  Both the '''1-man''' and '''south''' may each be called for ''shominkan'', before making a discard.  

  Naturally, this must be done one at a time, following the proper procedure for kan.

*If a kan dora would be delayed, such as for an open kan or added kan, a kan dora is revealed after a discard or after a kan call.

Under some rulesets, such as in [[tenhou.net]] and [[Mahjong Soul]], an alternative is used: so long as a kan does not change the hand's possible winning tiles, the kan is allowed. (I.e., even if a kan would change a possible interpretation of the hand, it is allowed if the waits do not change.)

The nature of [[dora|kan dora]] makes the call for kan inheriently risky.  With this in mind, some quick assessment is needed before making such a call.