Do you riichi?

[Krabman]

It could've come out of 455 or 556 shape.

[Referee]

Yeah. Could be from these shapes. Say 556 Sou, 468 Man. Draw 4s, discard 5. Draw 7m for tenpai, discard 4m. Riichi. Just one of the many possibilities.

[Mauro]

There is something beside kamicha discarding 5s just before riichi that makes you think it could belong to a 556 or 455?

(By the way, it was a wait.)

[Krabman]

I might be missing something, but not really.

In general, all middle suit tiles discarded out of someone's hand in mid-game are very likely to come out of various shapes. It could be a completed set, taatsu or someone could just be trying to fool you with karaten (swapping two identical tiles). A lot more context is needed to make more precise judgement - discard piles, open melds etc.

45m ryanmen in kamicha's hand (your last screenshot) is a perfect example of the above mentioned theory.

Hand reading like that is some advanced stuff, though. And you can't always rely on it, ESPECIALLY when you're playing with beginnners who often don't know what they're doing. I'm a beginner myself (I have yet to make it past 2 Dan), so I will stop here

This guy has a great video that covers many interesting topics, including the basics of hand reading:

Video

[Gnom]

6m looks dangerous, I'd only discard it if everything else looked as dangerous. I don't want to deal in a dealer riichi ippatsu and I don't need the points. 1s is safe against the dealer, and even though it's the dora there are already 3 outs which makes it less likely to be somebody else's winning tile if they have a ryanmen and you have two which makes it likely for somebody to be waiting on it with a shanpon. You still have a decent iishanten so who knows, you may even get your tenpai back...

[Mauro]

Thanks for the video, I'll watch it as soon as I have time!

6m looks dangerous

Just because it's neither safe nor suji, or there are other reasons it looks dangerous?

if they have a ryanmen and you have two which makes it likely for somebody to be waiting on it with a shanpon

Sorry, I don't understand what do you mean here...

[Gnom]

Just because it's neither safe nor suji, or there are other reasons it looks dangerous?

The fact that the player's last "conscious" discard is a 4m may indicate that they thought they had a use for it until the last moment, which may indicate a 344 or 445 pattern. They'd hold on to it because it would give them a wider iishanten (245 or 346 plus their other pair) but would choose to discard the 4 upon reaching tenpai. In technical words, the 4 is a matagi suji for either a 2-5 or a 3-6 wait. This kind of reading is far from accurate, but it gives you a hint. In this situation I would think that the 2-5 wait had a higher probability because the player discarded the 7m before the 1m, which I may indicate they thought it less useful, but I wouldn't dare to try and see which one it is. If the 1m is tsumogiri then that goes in favor of a 36 wait : in this case I'd say the 7 is more likely to be an urasuji (part of a 457 pattern indicating a final 3-6 wait) than a senkisuji (part of a 347 pattern indicating a final 2-5 wait).

Sorry, I don't understand what do you mean here...

Ah sorry I'd just woken up when I answered and didn't write a clear message (also failed to notice there already were answers that covered what I said). I meant that there are already three 2s out which makes the 1 less likely to be part of a ryanmen (1-4 wait) for one of the other players if they were tenpai, since they'd need a 2 and a 3 and there are few 2s. Also, since you have two 1s yourself it's less likely that someone is waiting for one to win with another shape : shanpon (wait on two pairs to make a triplet and a pair) is impossible since you have two 1s and the dealer discarded one. The only left is tanki (pair wait) but even that's unlikely. That makes the 1s a pretty safe tiles to discard despite being the dora, and it also leaves you with a decent hope to still win the hand !

[Mauro]

It's still early in the hand; I'm last in South 2 over 6000 points behind third, and I have almost all the hand in front of me. Which is better?

1) riichi, so I have three han instead of two, and hope in ippatsu, tsumo and uradora, but I warn my opponents I'm ready.
2) wait hoping for a dora for points, a terminal or an otakaze, then riichi.
3) don't riichi: the win is small, but I don't warn my opponents.

If immediate riichi, does it make any difference discarding or ? I already discarded one bam and none dot, but so early in the game I don't think that really says a lot about my wait, also given the potential bam wait is a 7.

[or2az]

With those point totals, I personally wouldn't worry about my opponents knowing I'm ready.
If they decide to bail, fine. Going for chiitoitsu, they have no idea what I'm waiting for and might toss me the winner.
I would riichi and toss the , although the may be equally as good.
Your choice #1 sounds good to me. I need points.

[Mauro]

Any reason you would toss instead of ?

(I riichied, tossed and ended in a draw.)

[or2az]

Not really. Since the hand has a few more dots than bams, including 2 fives and 2 sixes, maybe the opponents don't have a lot of dots, and no fives or sixes, and might toss a stray 7 as a result. Just a feeling. Who knows. They may have the 89 and keep the 7.

[Mauro]

This is more a "How do you riichi?", than a "Do you riichi?":

- discard and wait on : this way, I have 7 outs and a dora.
- discard and wait on : I only have 3 outs, but (1) if I win is sanshoku, for one more han (two for sanshoku, but I discarded a dora) and (2) shimocha already discarded a , so later on it could be discarded as safe tile against him.

[Krabman]

My 3 cents: since there's 1 Dora, I'd go for ryanmen here. The points are pretty even so the priority is to maximize your winning chances. Kanchan would be useful if you needed a Haneman late in South round OR if you had no Dora.

[Mauro]

Couple of cases in my last game:

20160205 (12a).jpg (65.85 KiB) Viewed 16798 times

South 3, I'm second with a nice lead on third (6000: not so good, at least mangan would be better, but neither so bad) and not so behind first (4900); I can riichi, but discarding or , which are not safe against shimocha.

The wait isn't good, and the hand quite cheap, but if I don't riichi here could mean give up on winning this hand (since the only safe tile is , and if I don't riichi because I don't want to discard crak then maybe later in the game I wouldn't still know if they'are safe); I have three safe tiles, so defending could work.

Since he didn't discard any crak it could be something colored, but so early in the game with a closed hand I think it's likely he just has few crak in hand, or all the craks he has are useful.

Also, ippatsu: if I pay now, it's an additional yaku.

(I riichied and paid 8000 due to riichi dora ippatsu uradora, he was waiting on ; with more time to think about what I wrote above, I think it'd be better not to riichi.)

20160205 (12).jpg (65.15 KiB) Viewed 16798 times

Another case: I'm third, 7500 behind second and 4600 above fourth; I already have sanshoku, so I can go dama, but that's a cheap hand; with riichi, it's at least 5200 (enough to be second if I ron from kamicha), more if I hit ippatsu and/ora uradora. With ippatsu or a single uradora, I'm second.

(I riichied, ron'd from shimocha with no ippatsu or uradora and ended third.)

[Krabman]

I think Riichi with that last hand was a good play.When exactly did the Ron happen? Were Toimen/Kamicha aggresive? Can you post screenshots of that Ron?

Tsumo would have given you 2nd place so I'm wondering if there had been time for that.