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Riichi strategy (view source)

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In addition, going from [[iishanten]] to tenpai can take a while. Even with great [[ukeire|tile acceptance]], you will often need multiple turns to do so. (Of course, this is dependent on luck.)
In addition, going from [[iishanten]] to tenpai can take a while. Even with great [[ukeire|tile acceptance]], you will often need multiple turns to do so. (Of course, this is dependent on luck.)
*If an iishanten opponent decides to attack into your riichi, you have the speed advantage. They will often need to spend multiple turns to reach tenpai. Therefore, they may need to spend multiple turns discarding dangerous tiles, which could be tiles you could ron off of. You could also tsumo before they reach tenpai, or win after they get tenpai.
*If an iishanten opponent decides to attack into your riichi, you have the speed advantage. They will often need to spend multiple turns to reach tenpai. Therefore, they may need to spend multiple turns discarding dangerous tiles, which could be tiles you could ron off of. You could also tsumo before they reach tenpai, or win after they get tenpai.
*If an opponent at iishanten decides to fold, you'll have one less player to worry about.
*If an opponent at iishanten decides to fold, you will have one less player to worry about.


Due to these advantages, a player who declares riichi first will often exert pressure on the other players. Therefore, other players may choose to give up their hands. Of course, this is not guaranteed, especially if the point standings force some other players to take on offense at all costs. However, you will still have the advantages listed above.
Due to these advantages, a player who declares riichi first will often exert pressure on the other players. This, in turn, can make other players give up their hands. Of course, this is not guaranteed, especially if the point standings force some other players to take on offense at all costs. However, you will still have the advantages listed above.


Conversely, a chasing riichi (riichi after another player has declared riichi) is weaker for the same reasons.
Conversely, a chasing riichi (riichi after another player has declared riichi) is weaker for the same reasons.  


=== Hand shape and waits ===
=== Hand shape and waits ===
Once a hand reaches tenpai, the chance of winning largely depends on the [[machi|tile waits]]. Hands waiting on three or more tiles, such as [[ryanmenten]] or [[sanmentan]], have a favorable chance of winning, while one tile waits like [[kanchan]] or [[tanki]] are less likely to win.  
Once a hand reaches tenpai, the chance of winning largely depends on the [[machi|tile waits]]. Hands waiting on three or more tiles, such as [[ryanmenten]] or [[sanmentan]], have a favorable chance of winning, while one tile waits like [[kanchan]] or [[tanki]] are less likely to win.  


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=== Hand lock ===
=== Hand lock ===
By declaring riichi, the hand is locked - you cannot upgrade the hand to improve the wait or gain yaku.  
By declaring riichi, the hand is locked - you cannot upgrade the hand to improve the wait or gain yaku.  


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{{#mjt: 123m345p888p4449s}} Waiting for: {{#mjt: 9s}}
{{#mjt: 123m345p888p4449s}} Waiting for: {{#mjt: 9s}}


You could upgrade the hand to a two-sided or better wait with: {{#mjt: 14m235679p2356s}}, which is up to 48 tiles. Of course, this number is reduced for every opponent discard, so keep note of that. You must also be wary of [[furiten]]. As the round progresses, you should be more willing to riichi; you don't have as much time to wait for an upgrade.
You could upgrade the hand to a two-sided or better wait with: {{#mjt: 14m235679p2356s}}, which is up to 48 tiles. When considering the number of upgrades, you should consider every visible tile. You must also be watch out for [[furiten]].
 
As the round progresses, you should be more willing to riichi than to wait for an upgrade; you don't have as much time to wait for an upgrade.
 
=== Defense ===
The hand lock prevents you from defending, which is the biggest risk of declaring riichi. Often, the reward is worthwhile (i.e., it's often best to keep tenpai instead of defending). But if the risk of dealing in is greater than riichi's extra value, then it can be a bigger point of concern.


Also, the hand lock prevents you from defending, which is arguably the biggest risk of riichi. Often, the reward is worthwhile. But if the risk of dealing in is greater than the reward of winning the hand with additional value, then it can be a bigger point of consideration.
For example, say it is South 2, you are in 2nd place, 1st place is 16000 points ahead, but 3rd is catching up. You shouldn't riichi with an otherwise [[pinfu]]-only hand, since the extra 1000-1900 points will not impact placement, but dealing into 3rd can cause you to drop down placement.


=== Furiten ===
=== Furiten ===
{{main|Furiten}}
{{main|Furiten}}


Declaring riichi means that, if the player declines the first possible ron, they enter permanent [[furiten]]. A damaten hand would only enter furiten until the dama player's next discard.
Declaring riichi means that, if the player declines the first possible ron, they enter permanent [[furiten]]. Meanwhile, if a damaten hand skips a win, it is only in furiten until the next discard.


First, damaten has better control over [[yasume]]. If a riichi hand wins off a bad wait, you have to accept it or enter furiten. However, since riichi adds an average of around 1.5 han, this is only an issue if the waits differ by 3+ han. Even then, you may want to riichi despite this.
First, damaten has better control over [[yasume]]. If a riichi hand wins off a bad wait, you have to accept it or enter furiten. However, since riichi adds an average of around 1.5 han, this is only an issue if the waits differ by 3+ han. Even then, you may want to riichi despite this.
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When the game is closer to its end (generally around the second half, but may be earlier if particularly large wins and losses have been going on), point standing becomes more of a concern. If the game could end on the next round, gaining +1000 points to go from 3rd to 2nd becomes much more valuable. At this stage, players who are ahead may not want to riichi, as the risks are amplified, among other considerations.
When the game is closer to its end (generally around the second half, but may be earlier if particularly large wins and losses have been going on), point standing becomes more of a concern. If the game could end on the next round, gaining +1000 points to go from 3rd to 2nd becomes much more valuable. At this stage, players who are ahead may not want to riichi, as the risks are amplified, among other considerations.


In other words: in the earlier end of the game, going for raw points is often the best play. In the later end, aiming to retain (or improve) your placement can matter more than the points themselves. This balance will depend on the game's [[oka and uma]] settings.
In other words: in the earlier end of the game, going for raw points is often the best play. In the later end, aiming to retain (or improve) your placement often matters more than the points themselves. This consideration will depend on the game's [[oka and uma]] settings.


=== Point standing ===
=== Point standing ===
When the game is closer to its end, point standing can affect the decision to declare riichi or not.
When the game is closer to its end, point standing can affect the decision to declare riichi or not.
*Players that are ahead will be more cautious. Late in the game, increasing their lead will not matter as much, while the risk of dealing in matters more. Meanwhile, players who are behind will want to riichi to catch up. Players in the middle should analyze their own specific situations to determine if riichi is right.
*Players that are ahead will be more cautious. Late in the game, increasing their lead will not matter as much, while the risk of dealing in matters more. Meanwhile, players who are behind will want to riichi to catch up. Players in the middle should analyze their own specific situations to determine if riichi is right.
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=== Winning chance ===
=== Winning chance ===
Pressing players to defend will lower your chance of winning. Assuming a dama hand has a yaku (i.e. it can ron), declaring riichi will generally lower your winrate by about 40%. Therefore, if winning matters and the extra score does not matter you should dama. Also, with valuable hands (mangan/haneman or above), dama is usually better.
Pressing players to defend will lower your chance of winning. Assuming a dama hand has a yaku (i.e. it can ron), declaring riichi will generally lower your winrate by about 40%. Therefore, if winning matters and the extra score does not matter you should dama. Also, with valuable hands (mangan/haneman or above), dama is usually better.


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