I was playing riichi mahjong with the gamedesign.jp Flash game and just before my turn when I would draw the last tile I got into this situation:

Last discard: 7 sou. My hand: 5 sou, 6 sou, 7 sou, 8 sou, 9 sou, green dragon, green dragon, open melds: 7 pin, 8 pin, 9 pin, 1 man, 1 man, 1 man.

At last, it's mine! — I thought and clicked ron expecting to win the game as with the new 7 sou I would have the required 4 melds and a pair:

  • The two open melds: chii and pon.
  • Chii: 5 sou, 6 sou, 7 sou.
  • Chii: 7 sou, 8 sou, 9 sou.
  • Pair of green dragons.

But instead of winning, this message popped in front of me:

Error: No multiplier

What are multipliers, and why the lack thereof impedes me from calling ron?

Then I tried the other option, chii and selected the tiles I wanted in it, resulting in exactly the same set of melds described above, but with another one of them open.

I expected at this point that I should have win... since I got 4 melds and one pair, and my hand looks like it has 4 melds and a pair, but the game disagrees and expects me to discard something.

My turn. My hand: 7 sou, 8 sou, 9 sou, green dragon, green dragon. Open melds: 7 sou, 5 sou, 6 sou, 7 pin, 8 pin, 9 pin, 1 man, 1 man, 1 man.

Being left with no other option, I click in wathever tile, for instance the 9 sou and the match ends in a draw, with me and left player in tenpai.

What happened? Why couldn't I call ron? I am missing something or is it a bug in the game? And what about using chii instead?


1 Answer 1


In order to win with ron or tsumo, your hand needs to have a yaku, in addition to having four sets and a pair (except for 7 pairs and 13 orphans hands). You can think of yaku as a specific pattern in the hand or a specific way to complete the hand. For example, tanyao requires that all of your tiles are numbered tiles between 2-8 (inclusive). Dora does not count as yaku.

Not directly related but you might run into this issue sooner or later: another requirement for winning with ron is that you must not be in furiten. There are three types of furiten and they are a bit complicated, so I will let you read about it from your favorite rule guide. Note that furiten never affects your ability to win by tsumo.

  • Dammit! This just happened to me again in a later game when I could have called riichi... if I did I would have a yaku and I could have successfully called ron, but I didn't know that was a requirement. About not winning with chii, I guess it's because chii forces you to discard a tile so you can't win by calling chii?
    – Alicia
    Apr 30, 2017 at 1:23
  • @Alicia The short answer to your last question is yes, by calling Chii, you are implicitly stating that you cannot go out (by ron) with the hand the tile would make. The same thing applies to Pon as well and technically to Kan too (as going out immediately after declaring a Kan would be tsumo, not ron) Apr 30, 2017 at 2:25

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