Peter Gao

I am a code writer, pickleballer, video gamer, manga reader, and graphic design dilettante. I love and suck at Riichi Mahjong.

This is the “Standard” ruleset as I learned from Koichi N. It’s a 4-player shuugi riichi mahjong ruleset.

Major Rules

These are the rules that commonly affect gameplay.

  • Ari-ari: kuitan and atozuke are on.
  • Abortive draws are
    • off if hand-shuffling
    • on if playing on auto-table, except for 4-riichi.
  • Kiriage Mangan is on.
  • Agariyame and tenpaiyame are off.
    • furthermore, all-last must end with a non-dealer win. Dealer no-ten leads to a repeat.
    • if 1st player has less than 31,000 pt, west extension is on until 1st player has no less than 31,000 pt. No North extension.
  • Regarding round winds:
    • The opposite wind is also a round wind. I.e., in East round, West is also a round wind. (“tonshaaba, nanpeiba”)
  • Regarding aka:
    • there are 2 red fives in each suit.
    • Red fives give +1 han and +1 shuugi only if the hand is closed.
  • Regarding extra dora indicators:
    • if the dice roll is 16, 11, or 66: 3 dora indicators.
    • if the dice roll is 22, 33, 44, or 55: 2 dora indicators.
    • otherwise, 1 dora indicator.
  • Open Riichi is on and free (no need to bet 1000). Only reveal tiles relevant to the wait.
  • Basengo: honba bonus is 500 per player.
  • Wareme is on.
  • Pinfu-tsumo is worth 1-han-30-fu (instead of 2-han-20-fu)
  • Chiitoi is worth 30-fu (instead of 25-fu)
  • These local yaku are on: Kanburi, Sanrenko, Renhou (Yakuman), Shiisanpuutaa (Yakuman).
  • Nagashimangan is a special win.
    • this means yakitori, honba, wareme, etc. are all applicable to a nagashimangan win.
  • Regarding yakuman:
    • yakuman may stack (except with kazoe yakuman)
    • 13-sided kokushi, 9-sided chuuren, daisuushi, and suuanko tanki are double yakuman
  • Chonbo penalty is a special reverse mangan. I.e., [-2000/-4000] for non-dealer, and [-4000 each] for dealer; this also ignores wareme, honba, etc.

Shuugi

Each chip is worth 5000 points.

  • Menzen only: each of ippatsu, aka, and ura is worth 1 chip.
  • Yakitori is worth 3 chips paid to the table
    • Re-yakitori: if no one is yakitori, everyone becomes yakitori again.
  • Yakuman shuugi is 20 chips if ron, and 10 chips each if tsumo, for each count of yakuman. Applies to kazoe yakuman.
  • Tobi: 2 chips in the East round, 1 chip otherwise.
    • in case of multi-ron, chips go to the first ron that caused the bust (in atamahane order)

Oka and Uma

Oka is 20k total. I.e., 25k start -> 30k return.

Uma is paid in chips:

  • 9/1/-3/-7 (if the 2nd place is below 30k)
  • 6/2/-2/-6 (all other scenarios)

House rules

At my place, I usually play with these modifications/clarifications:

  • wareme is off
  • split uma (if triple tie, round down).
  • If you are in riichi, you can peek at adjacent players’ hands (even if you can kan)

We follow WRC’s definition of chonbo and dead hand for regular penalties, except with the following changes:

  1. chonbo penalty is always 2 chips paid to each other player (yes, it’s a severe penalty given that chips are worth 5,000 each).
  2. an empty win call without revealing the hand results in a dead hand, NOT chonbo.

Updated: