Riichi: Difference between revisions

You are able to declare a closed [[kan]] after a riichi. When this is legal will depend on the ruleset; improper calls may be subject to [[chombo]]. See [[Kan#Kan during riichi|Kan during riichi]] for more details. Even if the kan is legal, you may or may not want to declare one.

Given the rules, riichi is compatible with all other yaku.  Likewise, riichi and double riichi cannot be combined as they are essentially the same yaku.  It just happens that double riichi is a specific instance of riichi.  Per rule and definition, it is impossible to attain ippatsu without riichi.

Once again, the prospect for [[rinshan kaihou]] to work with riichi is dependent on the legality of the [[Kan#Kan during riichi|kan during riichi]]. With computer interfaces, this rule may be enforced by disabling a player's ability to call the kan during this situation.  However, with actual tiles, a player must be aware of this legality.  Otherwise, chombo may be enforced instead.

Calling riichi is an optional play.  Therefore, players often have to make various considerations when it comes to using riichi. Often, this will depend on the discarded tiles, how early or late in the hand, the hand value, and/or the player's hand composition. If possible, a player may opt not to use riichi at all and instead employ the strategy of [[damaten]].

For any given hand, more than one player may call riichi.  Subsequent riichi calls after the first is called '''oikake riichi''' {{kana|追いかけリーチ}}, or "chasing riichi". Oikake has one distinct advantage of an ippatsu ron chance against any previous riichi hands before taking a draw. After all, defense is no longer a factor to those hands, as they are committed to discarding non-winning tiles.  The hands are essentially engaged in a "riichi duel" provided that they have different waiting tiles. Under many rulesets, the hand aborts in the event for all players to have declared riichi via [[suucha riichi]].

Riichi may actually be called if all waiting tiles are rendered unavailable. A hand in this state is rendered as [[karaten]]. In this state, the hand is not winnable as the number of available winning tiles is zero.  Such calls may be made by mistake, or intentionally invoked to cause players to defend.