Tohai S1 is completely subbed!


Tohai Season 1

xkime previously subbed episode 1 of the live action adaptation of Shinasaka’s Tohai manga, since then he has moved on to subbing it on Rakuten’s (free) streaming service viki and has just finished subbing the final episode of season 1.

Season 2 is also available here some of the episodes have been subbed by someone else, but I think the subtitles need a bit of editing before they become watchable.

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Identifying Dangerous Suji

Suji are a popular defense strategy; so popular, in fact, that suji traps are an effective anti-defense. We would like to increase the yomi level and create an anti-anti-defense by identifying when suji traps are likely. Are there situations in which suji are more dangerous? Are they really traps, or are they just incidental discards?

Prominent authors actually disagree on this. Some claim that suji discarded after riichi are more dangerous, while others claim that suji discarded before riichi are more dangerous. The general agreement is that the tile discarded immediately upon declaring riichi is dangerous.

Who’s right? Do you think there’s a difference? Using the Tenhou game logs database, we can examine riichi hands and their discards to finally answer this question.


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Results of the 1st North American Riichi Open, in Montreal [CA]

Hello there!

Running a tournament for the first time is really a special experience. While I have been busy with stuff, I did want to get the first article out as soon as possible.

MONTREAL (QC), CANADA — 12 competitors took part in the first open* mahjong tournament using riichi rules. Dominating Day 1 was a member of Montreal’s new wave of talent, Claudel B., with all first places. On Day 2, he managed to maintain his advance by retaining his points as well as he could. Congratulations to Claudel, the Canadian Champion, who has won a Junk Mat as a prize with his +112.3 points over 8 matches. Filling the podium are Sean H. from Waterloo (ON) in 2nd place with +71.1 points, along with a tie for third place between Marc-André D. from Montreal and Luke M. from Rochester (NY), USA with +63.2 points each.

The tournament welcomed 3 players from the United States, as well as one from outside the province of Quebec, proving that Montreal is definitely going to continue growing as one of the continent’s poles of attraction for future growth at the club and in tournaments aiming to welcome players from Canada, the Unites States, as well as eventually Europe and abroad. The rules used were a suitable hybrid between local Montreal rules and practices (e.g.: inclusion of daisharin), and the rules used at the 2014 WRC in Puteaux, France (atama-hane, 15-5 uma, tenpai-renchan, no kazoe yakuman, no aborts, no weird stuff [so no ryanhan shibari or paarenchan]), while fixing the rules regarding tile exposures from any wall and the call priority (3.0 seconds BUT only 0.5 seconds to override).

The organizer (and author of this article) says: “Making sure this first tournament was a success was very important not only to me, but to the participants involved as well as some non-participants who provided critical support. My goal was to launch the first of many tournaments (not just for us but to see similar initiatives across the continent) that met the same organizational standards as tournaments in Europe (3 month advance notice, open to all, 16+ participants). While that goal was almost accomplished, historically speaking, Denmark also had 12-person tournaments for a while in 2008. I can therefore say I am totally satisfied by the event’s success, its result, as well as its eventual future.”

Speaking of the future, the next North American Riichi Open in Montreal can be planned for in advance: the date is 90% certain to be June 4-5, 2016 (the 10% uncertainty is due to scheduling away from the F1 Grand Prix weekend).

We hope to see more of you here next year, you might be able to stand on the podium too, the replica podium in front of Montreal’s Olympic Stadium as seen below!


To contact the organizing team for information and planning for the next event in 2016, please contact us using this year’s tournament e-mail, at: tournoi2015 ## riichi # ca (substitute usual symbols in the address). We plan on informing people well in advance with the explicit goal of obtaining registrations as soon as possible for next year, with an early bird special prior to February 29, 2016.

Rank Name Score (thousands)
1 Claudel B. 112.3
2 Sean H. 71.1
3.5 Marc-André D. 63.2
3.5 Luke M. 63.2
5 Senechal D. 56.5
6 Shan K. 37.8
7 Kyuu 28.7
8 Alex B. -21.7
9 Anne R. -30.4
10 Dasuke -38.9
11 Anne-Marie D. -167.7
12 Patrick M. -187.1


  • Article precision: the term “Open” (in English) or “omnium” (in French) implies not only the passive idea of letting anyone participate (no mattter their gender, age, race, nationality, or favourite ice cream flavour), but by inviting people openly to do so. There have been micro-tournies, league-type “tournies”, and closed-club tournaments, as well as spontaneous things before: while acknowledging their existence, I believe the usage of “1st Open” on the continent was and is totally justified, w.r.t. Japanese mahjong. Here’s to hoping that the “2nd NARO” (even if it doesn’t use that name to advertise) will take place somewhere else prior to Montreal in June 2016.

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NA/EU Super Weekend: June 13/14 – Mahjong Study Session in Paris by Moriyama + First North American Riichi Open Reminder

Great news on both continents!

(Shameless plug)
In North America, the first North American Riichi Open is taking place in Montreal, Qc. (Canada). Registrations are still ongoing, contact for more information :)
(/Shameless plug)

In Europe, the professional player and president of the Japan Professional Mahjong League, Mr. Shigekazu MORIYAMA, is organizing two clinics in Paris the same weekend. From the French Fed’s forum:

The French Federation of Mahjong has the pleasure to notify you that the Tri Nitro Tiles and Magic Mahjong Social Pung clubs are co-organizing an event promoted as the first of its kind in France: a strategy course with a professional mahjong player as instructor!
This event, which will be held 2 weeks before the French Riichi Championship, is a great way to put all chances on your side to succeed at that competition!

The pro: Mr. Moriyama is nothing less than one of the founders and the actual president of the JPML, he is also one of the members of the World Riichi Championship Committee.

If you want to know more on this iconic player, you can read his interview on Part 1. Part 2.

Riichi Study Session (it isn’t mandatory to be present both days):

June 13, 2015 from 16:00 to 20:00, at the MMSP location: 33 rue Blanche, 75009 Paris
June 14, 2015 from 11:00 to 17:00, at the TNT location: 45-47 rue des pavillons, 92800 Puteaux

This course will be translated in English as it is open to all players of the EMA, who is supporting this project.
Entrance is free (no cost) for all registered players of the EMA.

For more information, please contact the MMSP and TNT presidents directly.

From Gemma, Representative of the JPML
From Oliv’, Chief of competitive activities of the FFMJ.

So no excuses people, time to get off your butts and go somewhere French-speaking for the weekend :)

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Benjamin Boas Leads in First Session of Good Players Club Tokyo Chomeijin

About GPC
Good Players Club is run by Katayama Masayuki and Baba Hirokazu and organizes public leagues and tournaments throughout Japan. Anyone who is a ‘productive member of society’, not a Jangoro (basically a hardcore mahjong gambler) and agree with their charter:

1: Good Players appreciate their opponents.
2. Good Players only criticize themselves.
3. Good Players have good humour.

are able to join.

In addition to their public leagues, they have a Chomeijin League in Tokyo and Kansai that’s only open to celebrities.

GPC 2015 - 1 out of 9 Sessions Played
Rank Name Total Games Played
1 Benjamin Boas (Mahjong Researcher) 152.4 4
2 Daisuke Takahata (Sega) 125.9 4
3 Koshiba Tetsuya(Mangaka) 87.7 4
4 Kazuhiko Tsuchiya(Announcer) 79.1 4
5 Hirokazu Baba(Writer) 57.4 1
6 Nobuyuki Fukumoto(Mangaka) 39.8 4
7 Nao Oikawa(Actress) 29.9 4
8 Tsuyoshi Koyama(Voice Actor) 28.4 4
9 Shinichi Oota(Keirin Cyclist) 24.1 4
10 Mitsuki Kono(Igo Professional) 18.8 4
11 kouji Shinasaka(Mangaka) 14.8 4
12 Manabu Senzaki(Shogi Professional) 2.4 2
13 Yoshitaka Munehiro(Horse Racing Pundit) -4.5 3
14 Keiji Hanasaki(Author) -40.9 1
15 Tomihiko Tokunaga(Sriptwriter) -56 4
16 Ryan Morris(Translator) -59.4 4
17 Masayuki Katayama(Mangaka) -60.1 2
18 Hiroyuki Murta(Mangaka) -82.2 4
19 Ginji Hideo(Singer) -153.6 4
20 Eri Mizuki(Substitute) -216 3

Full results:

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Unified Mahjong Terminology

Every time a new mahjong site pops it, it seems a new set of terminology is invented. To stop confusion we at Osamuko have created a new set of terminology for Japanese Mahjong. We will be updating all our posts with it in the coming years. We hope that other sites will also use it, but they probably won’t. Below is the list in Kanji – Romaji – UMT order

吃 – チー – chi – eat
碰 – ポン – pon – bump
槓 – カン – kan – bar
栄 – ロン – ron – glory

立直 – riichi – stand straight
七対子 – chiitoitsu – seven pairs
流し満貫 – nagashi mangan – drained slam
門前清自摸和 – menzenchintsumohou – doorfront pure self pick win
一発 – ippatsu – one shot
海底撈月 – haiteiraoyue – pull moon from the bottom of the sea
河底撈魚 – houteiraoyui – pull fish from the bottom of the river
嶺上開花 – rinshankaihou – flower blooms on mountaintop
搶槓 – chankan – snatched bar
双立直 – daabururiichi – double stand straight
平和 – pinfu – flat win
一盃口 – iipeikou – one cup mouth
三色同順 – sanshokudoujun – three colors same arrangement
一気通貫 – ikkitsuukan – one breath pierce through
二盃口 – ryanpeikou – two cup mouths
対々和 – toitoihou – matched win
三暗刻 – sanankou – three hidden quarters
三色同刻 – sanshokudoukou – three colors same quarter
三槓子 – sankantsu – three bars
断么九 – tanyaochuu – snapped terminals
役牌 – yakuhai – position tiles
混全帯么九 – hunchantaiyaochuu – mixed all carrying terminals
純全帯么九 – junchantaiyaochuu – pure all carrying terminals
混老頭 – honroutou – mixed old men
小三元 – shousangen – small three origins
混一色 – honiisou – mixed one color
清一色 – chiniisou – pure one color
国士無双 – kokushimusou – patriot without parallel
国士無双13面 – kokushimusoujuusanmen – patriot without parallel 13 faces
四暗刻 – suuankou – four hidden quarters
四暗刻単騎 – suuankoutanki – four hidden quarters single mount
大三元 – daisangen – big three origins
小四喜 – shousuushi – small four happinesses
大四喜 – daisuushi – big four happinesses
字一色 – tsuuiisou – characters one color
清老頭 – chinroutou – pure old men
緑一色 – ryuuiisou – green one color
九蓮宝燈 – chuurenpoutou – nine lotuses and treasured lanterns
純正九蓮宝燈 – junseichuurenpoutou – perfect nine lotuses and treasured lanterns
四槓子 – suukantsu – four bars
天和 – tenhou – heavenly win
地和 – chihou – earthly win

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English Online Mahjong Events

PML Mugboney Mug

After 4 long months the PML Mugboney Mug Team tournament finally ended, the winner was Team /人◕ ‿‿ ◕人\ (Pronounced ‘keiyaku’). The tournament had 20 3 player teams, and was sponsored by the Pacific Mahjong League and This was the 2nd tournament organized by the Bugmoney team, for more events organized by them please keep an eye on!


The 3rd season of the World Riichi Mahjong League is nearing the end with 1 week remaining. Puyo (8D) is currently leading with a whopping 377.3 while 2nd and 3rd have 199.8 and 197.9 respectively

Full scores are:

Rank Name Points
1 Puyo 377.3
2 Benawii 199.8
3 Osamu 197.9
4 Cliff 138.9
5 xkime 111.5
6 XSA -28.9
7 fallensoul -93.8
8 Muller -110.8
9 Yazphier -122.6
10 oldpier -221.3
11 Kyuu -227.5
12 selfeater -300.5

The final games take place this Sunday (OR Saturday if you’re in North America) at 6AM UK time and the winner will take home $100. There will be a livestream at

The WRML are also looking for players for the next season, if you’re interested and are 4dan or higher on Tenhou, you can register your interest here:

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