Peter Gao

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

This is Shenyang Mahjong as I learned it from my friends. I will use riichi terminologies to explain the Chinese terminologies. Feel free to share with me any rule variations.

Deck and wall

  • Deck has 3 number suits, 3 dragons, and 4 winds; 136 tiles total.
  • Dead wall has 16 tiles. Every gang adds 2 tiles to the dead wall.

Requirements to win

  • Must have 4 sets and 1 pair
  • Must have all 3 number suits
  • Must have an open hand (i.e., having called chi, peng or gang)
  • Must have at least 1 terminal/honor tile
  • Must have at least 1 kezi (triplet/gang/angang) OR have dragons as your pair.

Below are examples of invalid hands:

1s1s1s2s2s2s3s3s3s4s4s5s5S5s

the hand doesn’t have all 3 number suits

1s2s3s1m2m3m1p2p3p1z1z1z2z2z

the hand is not open

4s5s6s4m5m6m6p6p6p7p7p2S3s4s

the hand doesn’t have any terminal/honor tile

1s2s3s1m2m3m1p2p3p2z2z4S5s6s

the hand doesn’t have any kezi nor a dragon pair

Hand Value Calculation

  • Base points: 2
  • Dealer always pays and wins double (x2)
  • Player who doesn’t have an open hand always pays double (x2)
  • Winning by hu (ron): x2
  • Winning by zimo (tsumo): everyone pays x1 (note: dealer pays/wins double, and closed-hand players pay double)
  • Duiduihu (toitoi): x8
  • Each dragon triplet in hand: x2
  • Each gang/angang in hand: x2
  • Gangshang Kaihua (rinshan): x2
  • Gangshang Pao (hu on discard after a gang): x2
  • Qianggang (chankan): x2
  • Waiting on only 1 kind of tile: x2 (e.g., 3s5s5s5s waiting on 3s4s does not qualify)
  • dice roll double: x2 (i.e., 1/6 chance)
  • last round is liuju: x2 (ryuukyoku -> next round win becomes x2)
  • during your first turn, you can meld 1 of each dragon 5z6z7z. This is considered a dragon kezi (i.e., it fulfills the kezi and honor requirements) and gives you x4 instead of the usual x2 from dragon kezi.
  • during your first turn, you can meld 1 of each wind 1z2z3z4z. This is considered a wind angang (i.e., you must draw a replacement tile, and it fulfills the kezi and honor requirements) and gives you x4 instead of the usual x2 from angang.

Special rules

  • Chitu (kuikae) is OKAY (e.g., chi 3S4s5s and discard 3s)
  • Zhahu (invalid win): the offender pays 8 points to each other player immediately; the hand is voided (like chombo).
  • you cannot call the fourth set unless it confirms duiduihu (i.e., naked tanki is only allowed for toitoi)
  • you do not need to show what your angang tiles are before the hand ends. You must show them after the hand ends (invalid angang is cheating).
  • skipping or discarding a tile makes you unable to call hu on that tile until your next draw (note this is different from furiten)
  • if dealer wins or liuju: dealership continues; otherwise dealership rotates. Tenpai-ness does not matter.
  • if 4 players discard the same tile in a row, the player who made the first such discard pays everyone 4 points immediately
  • when there are only 4 tiles left to draw (excluding the dead wall, which starts at 16 tiles), everyone draws in order to check if they zimo. If anyone does zimo, then it’s called haidilaoyue (haitei), awarding a x2 bonus. Notably, nobody makes a discard during this process (i.e., nobody can deal in).

Local variations

  • the x2 from liuju and double dice roll do not stack. Instead, any additional x2 gained this way is passed onto the next hand.
  • Revealing any tile that’s not part of your hand (e.g., by knocking over the wall) will be penalized. The offender pays 4 points to the pot for each tile revealed (next winner takes the pot).

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