Do you riichi?

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Mauro
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Do you riichi?

Post by Mauro » Sat Sep 12, 2015 9:04 am

http://tenhou.net/0/?log=2015091216gm-0 ... b69ba&tw=1

South 2: in the fifth step I was tenpai, waiting on 2-bam (three out) and 8-bam (three out); it wasn't a good wait, I was first with a good lead on third and fourt, so also to not lose the chance to defend I choose not to riichi, and both tiles were discarded; on the other hand, I was East, so chance of renchan. Was it right not to riichi?

(In East 4 I threw away tenpai, dealing in meanwhile; don't know why I missed it, or if I was just wary to discard dora, with none showing and left player potentially dangerous on bams.)

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Re: Do you riichi?

Post by or2az » Sat Sep 12, 2015 5:47 pm

South 2

3-crak 3-crak 3-crak 6-dot 7-dot 8-dot 2-bam 2-bam 7-bam 8-bam 8-bam 8-bam 9-bam

Since you decided not to riichi due to the bad wait of 2 tiles, one 8-bam and one 2-bam , why not change the wait when you drew the 4-bam on your next turn and especially when that last 8-bam came out and you drew the 4-bam again. There were still three 3-bam left.
At least you would have had a better shot at winning.

You also didn't have a yaku, so after drawing that first 4-bam early , and if you still decide not to riichi, you may have decided to toss the 9-bam and have tanyao.
It would move you back from tenpai, but the options of riichi, menzen tsumo, open tanyao, or playing it safe, would still be there for later.

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Re: Do you riichi?

Post by Mauro » Sat Sep 12, 2015 7:11 pm

You're right, I think I was short on time and I didn't noticed it; as for open tanyao, I was playing without it.

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Re: Do you riichi?

Post by Mauro » Wed Sep 16, 2015 11:00 am

I had an interesting hand: it's quite early in the game and I'm tenpai. If I ron my win it's 12k points, if I tsumo it it's yakuman. Riichi could make a ron worth something more, if I hit ippatsu or ura dora, but it'd let my opponents know I'm tenpai. On the other hand, if someone turns in defense I could improve my tsumo chance, and both my waits are half suji.

(In the end I didn't riichied, and left player won on a ron from front player; of my four outs, one was in left's hand, and the other three somewhere in the wall.)
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Re: Do you riichi?

Post by Iapetus » Wed Sep 16, 2015 12:27 pm

Declaring riichi increases your chances to tsumo. With suuankou it's standard to riichi to maximize your yakuman chances.

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Re: Do you riichi?

Post by Gnom » Wed Sep 16, 2015 1:57 pm

Image

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Re: Do you riichi?

Post by Mauro » Tue Sep 22, 2015 11:55 am

South 3, I'm in first place with a nice lead; I have just three outs (6-bam), which is half suji.
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Re: Do you riichi?

Post by Gnom » Tue Sep 22, 2015 5:24 pm

Only 3 of your outs left and only yasume so you're looking at a difficult 2000 points (3000 if tsumo) win where you're exposing yourself when you don't need either points or renchan, plus you have a pretty good potential for defense... For me that would be damaten and folding at any sign of danger, aiming at a quick win in S4. That discarded 3-sou won't help you much either.

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Re: Do you riichi?

Post by Mauro » Tue Sep 22, 2015 10:18 pm

I was wondering about suuankou (http://reachmahjong.com/en/forum/viewto ... ffe#p58911): would it be standard to riichi also if I were in tanki wait, with the four pon already in hand?

Edit: I wrote suukantsu, edited with suuankou.
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Re: Do you riichi?

Post by Referee » Wed Sep 23, 2015 3:09 am

You mean Suuankou. Suukantsu is four kan. Anyway, Suuankou Tanki is double yakuman (if allowed) whether by ron or tsumo, so I'd say damaten in this case.

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Re: Do you riichi?

Post by Mauro » Wed Sep 23, 2015 7:17 am

Fixed, thanks. What if it weren't a double yakuman (under EMA rules, it isn't; the only double yakuman is the big four winds).

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Re: Do you riichi?

Post by Mauro » Sun Sep 27, 2015 11:01 am

A couple of situations, with my considerations:
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1) I riichied (and lost to toimen), but I was unsure about that, and in retrospect maybe it would have been better not to riichi. If I win it's mangan, but I'm waiting just on dora: two outs, and dora isn't likely to be discarded with someone in riichi. If the 3-crak weren't in the pond, I think riichi is good.
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2) if I don't riichi, I'm first unless I win by ronning 8-crak from someone beside shimocha, otherwise I win; since toimen is less than 10k behind me, is East (so chance of continuance if he wins) and seems to be after something flushy, I think it's best to stay damaten and avoid risking dealing in toimen.

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Re: Do you riichi?

Post by Mauro » Sun Nov 08, 2015 10:01 am

I'm first, with a few points on second; kamicha just riichied; I can go with riichi pinfu two dora triple wait, but discarding 6-crak which isn't safe.
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Re: Do you riichi?

Post by Krabman » Sun Nov 08, 2015 3:17 pm

That's a very interesting push/pull situation. I have a lot to improve in that field myself...Anyway... here are my thoughts:

The hand is really tempting. Great wait. Dora 2 and only one 1s unaccounted for. Oya most likely doesn't have it. But with ippatsu/ura, getting a Mangan here is not hard. 45m ryanmen wait is possible. That 5s also points to a possible wait in Souzu.

We mustn't forget Toimen, who reeealy doesn't want Kamicha's renchan. If his hand is progressing nicely, he might push.

The question is - do you need to win here?

I don't think so. Even if Oya gets tsumo Haneman, you will not be too far behind and there's still your Oya turn to get him back. If you deal in - you might even fall to last place and he will still get renchan. The risk isn't worth taking, in my opinion.
Last edited by Krabman on Sun Nov 08, 2015 8:19 pm, edited 2 times in total.

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Re: Do you riichi?

Post by Mauro » Sun Nov 08, 2015 3:34 pm

Krabman wrote:45m wait is possible. That 5s also points to a possible wait in Souzu
Why that 5s points to a possible souzu wait?

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