Do you riichi?

Guides and beginner's help. If you're new to mahjong, this forum is for you. All questions are welcome - don't hesitate to ask.

Moderator: Shirluban

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.)

User avatar
or2az
Gold Boarder
Gold Boarder
Posts: 823
Joined: Tue Aug 20, 2013 5:10 pm
Location: USA

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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.)
Attachments
20150916.jpg
20150916.jpg (119.63 KiB) Viewed 14360 times
Last edited by Mauro on Wed Sep 16, 2015 4:48 pm, edited 1 time in total.

Iapetus
Senior Reacher
Senior Reacher
Posts: 195
Joined: Sat Jul 16, 2011 1:00 am

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.

Gnom
Senior Reacher
Senior Reacher
Posts: 122
Joined: Fri Feb 15, 2013 9:15 am
Location: 名古屋市

Re: Do you riichi?

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

Image

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.
Attachments
20150922 (4).jpg
20150922 (4).jpg (120.55 KiB) Viewed 14327 times

Gnom
Senior Reacher
Senior Reacher
Posts: 122
Joined: Fri Feb 15, 2013 9:15 am
Location: 名古屋市

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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.
Last edited by Mauro on Wed Sep 23, 2015 7:17 am, edited 1 time in total.

Referee
Expert Reacher
Expert Reacher
Posts: 382
Joined: Sat Apr 24, 2010 6:24 pm

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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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).

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

Re: Do you riichi?

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

A couple of situations, with my considerations:
01.jpg
01.jpg (120.41 KiB) Viewed 14276 times
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.
02.jpg
02.jpg (125.75 KiB) Viewed 14276 times
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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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.
Attachments
20151108 (32).jpg
20151108 (32).jpg (122.08 KiB) Viewed 14163 times

Krabman
Senior Reacher
Senior Reacher
Posts: 121
Joined: Sun Jun 15, 2014 9:34 pm

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.

Mauro
Senior Reacher
Senior Reacher
Posts: 119
Joined: Tue Sep 08, 2015 10:09 am

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?

Post Reply