What ruleset is used for the Prefecture and National tournaments?

Question

Riichi mahjong has a number of different variants in terms of rules, scoring, allowed hands, etc., even at the pro level in real life. Most of these rarely come into play, but when they do they can have a big impact on the game. In the Saki anime, the rules they are playing with are sometimes referenced (for instance, no multiple yakuman, robbing a closed kan for kokushi musou is allowed, and pao is applied for rinshan kaihou).

However, a lot of the other, more mundane rules aren't shown in the anime (e.g. whether a player may call for a redeal if they start with a lot of terminals and honors, the validity of open tanyao hands, whether renhou, shiisanpuutā/shiisuupuutā are allowed, etc.). Is there any official word on what ruleset is being used for these tournaments?

Answer 1

It's been two years since this question was posted, but since there's been no answer so far and a lot has happened since then, I thought I might have some fun and see what I could find.

Parts with * means that it happened outside of a tournament, e.g. at a training camp. For references I'm using the Saki and Achiga-hen mangas/animes only.

Basic yaku/han rules

• Kuitan (open tanyao): Yes

  

• Ippatsu (one-shot): Yes

• Dora: Red (four), ura, kan, kan-ura
• Sanrenkou/Suurenkou (3 or 4 consecutive triplets): No (Ch. 52 Saki)

Scoring rules

• No-ten penalty: Yes
• Tobi (going bust): Negative score, not zero (Ch. 42 Kana)
  • Koromo, being the sadistic loli she is, purposely cheapens her hand to drop Kana's score to exactly zero.
• Tiebreaker after score: First dealership (Achiga Ch. 20 Awai)
  • Awai ignores a potential sanbaiman since it would make her tie in points with Shizuno, and because Shizuno's dealership was earlier Awai would end up behind.
• Uma/oka (bonus points based on final placements): No (Ch. 11)
• Double wind pair: 4 fu (Ch. 47 Saki)
  • Saki gets a 1 han 110 fu, which is only possible with this rule due to 102 fu being rounded up. For rules where this is 2 fu, it would be stuck at 100 fu.

Yakuman rules

• Robbing a closed kan for kokushi: Yes (Ch. 36 Saki)
  • Saki avoids calling kan on a set of wests, being suspicious of Yumi's kokushi (which was 1-shanten at the time).
• Double yakuman: No (Ch. 43, Ch. 51 Kana)
  • Hisa explains that there are no double yakumans in "this year's rules", so the rules most likely change from year to year.
• Allowed yakuman: Either mentioned, attempted or actually won
  • Riichi tsumo toitoi Suuankou/Four closed triplets (Ch. 3 Saki*, Ch. 20 Kaori, Ch. 51 Kana, Ch. 125)
  • Kazoe-yakuman/Counted yakuman (Ch. 44 Kana, Ch. 52 Saki, Achiga Ch. 20 Himeko)
  • Kokushi musou/Thirteen orphans (Ch. 4 Saki*, Ch. 42, Ch. 48 Kana, Ch. 53 Yumi, Ch. 125, Ch. 140 Yukiko, Anime Ep. 21 Kaori)
  • Chinroutou/All terminals (Ch. 68 Hiroe)
  • Shousuushi/Little four winds (Ch. 56 Hatsumi, Ch. 89 Hatsumi)
  • Daisuushi/Big four winds (Ch. 125)
  • Tsuuiisou/All honours (Ch. 125)
  • Daisangen/Big three dragons (Ch. 13 Mai, Achiga Ch. 15 Takami)
  • Tenhou/Win on first dealer draw (Ch. 71)
  • Chiihou/Win on first non-dealer draw (Achiga Ch. 19 Awai)
  • Ryuuiisou/All green (Ch. 58 Kaori*)
  • (Possibly more)

General play rules

• Daiminkan pao/sekinin barai (responsible for open kan rinshan): Yes (Ch. 52 Saki)
• Temporary furiten: Yes (Achiga Ch. 6 Shizuno)
  • Shizuno could only win on 1-sou with a 2-3 wait, but could not ron in one of the rounds due to a 4-sou played earlier that round. Later she ignores a ron off one player in order to win off another.
• Taahai (penalty for having too many tiles): Yes (Ch. 62 Maho*)
  • In the training camp Maho reaches to draw a tile even though she's dealer before the first discard.
• Empty riichi: Yes, and counts as tenpai on draw (Ch. 27 Hisa)
• Furiten riichi: Yes (Ch. 137 Yukiko, Anime Ep. 21 Mihoko)
  • Yukiko draws her winning closed 2-man but contemplates a furiten riichi to gain more points. Mihoko actually pulls off a furiten riichi against Hisa in the individuals, and wins with it.
• Calling pon on a tile you just discarded: Yes (Achiga Ch. 8, Teru)
• Dealer can extend leadership after last round: Yes (Achiga Ch. 10 Teru)
• Going west (extra round added if no player gets at least 30000): Yes (Anime Ep. 21)
  • Halfway through Ep. 21 Mutsuki explains how Nanpo was able to make a comeback once it entered the south round, despite it being a tonpuusen (east-only game). Note that no round is added if the top player ends on exactly 30000, as Saki did in Ep. 22.

Draw condition rules

• Kyuushuu kyuuhai (starting hand has 9+ terminals/honours): Yes (Ch. 140 Yukiko)

  • Yukiko says that "normally, one would abort the round" (普段なら流すところだけど), which suggests that she has the option to do so.

  

• Suufontsu renda (all players discard same wind tile on first round): Yes (Ch. 73 Yuuki)

  • Yuuki reaches tenpai on the first round, but is forced to abandon it since it would require discarding a west, drawing the round.

• (Possibly more)

Tournament room

• People allowed: The four players only (Ch. 11)
  • Presumably this refers to the competing schools only, since tournament staff are seen in the room later in the same chapter.
• Mobile phones: No point since they won't get any signal (Ch. 11)
• Stuffed toys: Yes
• Food: Yes
• Taking off shoes and socks: Yes
• Singing: Yes (Ch. 125 Choe)
  • The commentators go on to explain that this is allowed in European championships, but not for pro tournaments in Japan (interhigh is okay).
• Throwing a tile into the air then slamming it down: Nobody complained (Ch. 25 Hisa)
• Playing with tiles face down: Yes (Ch. 141 Megan)
• Playing left-handed: Yes (Ch. 138 Yukiko, discussed in Ch. 142)

Other rules

• Practice games for prefectural winners: Only against other non-prefectural winners (Achiga Ch. 3)
  • Similar rules seem to apply to the individual tournament (Achiga Ch. 7)
• Vanguard for team tournaments: Must be Japanese (Ch. 108)
  • This rule was recently changed, since up until now Rinkai had all five members being foreign (Ch. 106).