A player who needs only one more tile to complete his hand is said to be Tenpai. He may get the tile he needs to complete his hand in one of two ways:
- By going Tsumo; he draws the tile from the wall on his turn.
- By going Ron; he claims the tile as another player discards it.
The player completes his hand himself by drawing the tile he needs from the wall in his turn. He places it face upwards on the table, reveals his hand and says “Tsumo!”
When a player completes his hand by going Tsumo both the other players have to pay him a certain percentage of the total fine. This means that the burden of the cost is shared by both players (see Points and Payments).
A player who is Tenpai may, under certain circumstances, complete his hand by claiming the tile that he needs from another player when that player discards or reveals it.
When he the sees the tile he needs to complete his hand being discarded (or revealed) by another player he claims it by saying “Ron! ” He then shows his hand and his score is calculated.
The player who gave away the winning tile is the only one who has to pay. This means he has to bear the whole burden of the cost on his own. Ouch!
Note: the most common way the winning tile is given away is when it is discarded by a player at the end of his turn. However, there are some other cases when Ron may occur. These are:
- The player puts to one side the North Dora ($BKL(J), which another player requires to complete a hand such as Kokushimuso.
- A player converts an open Pon into an open Kan and another player goes Ron on that tile.
- A player who is waiting to complete Kokusimosoo can go Ron if the tile he requires is exposed by another player’s making a hidden Kan (ChyanKan).
When Can You Go Ron?
A player may go Ron if his hand contains at least one completed Yaku.
He may also go Ron if the tile he is waiting for also completes a Yaku (except for winds and dragons), provided no other non-yaku finishing combination exists. E.g:
Special care must be taken with these cases. Remember, if the hand already contains a hidden Yaku the player can go Ron any time. It is only where going Ron will create the only Yaku of the hand that the player must take special care. If a player makes a mistake with his finishing options when going Ron he will have to pay a fine (see Chombo).
One way to avoid this problem is to go Riichi.
Going Riichi – Buying the Right to Go Ron
If a player is Tenpai but has no Yaku in his hand, he may buy the right to go Ron, that is, he may go “ Riichi“. On his turn he takes a 1,000 score stick (Sentenbo) from his kitty and places it in the centre of the table just in front of his discard pile and says “Riichi! ” This warns the other players that he is ready to complete his hand. He then discards a tile (making sure it is the one he does not need to complete his hand). As he discards it he lays it sideways on against the last tile in his discard row. This also lets the other players know that he is ready to go out, and marks the point in the game where he went Riichi.
Note: A player cannot go Riichi at the very end of the game when there are less than three playable tiles remaining in the wall
Two Disadvantages of Going Riichi
The first disadvantage of going Riichi is that it removes the element of surprise. Going Riichi acts as a signal to the other players who will then begin to play carefully. They will check the discard row of the player who has gone Riichi and endeavour to throw away tiles that he does not need.
The second disadvantage of going Riichi is that the player commits himself to completing his hand as it is. He may not change his hand under any circumstances. However, he may improve its scoring potential by collecting Bonus tiles (see Bonus Tiles, Dora) and by going Kan on a tile that he takes from the wall (see Kan).
The Riichi Privilege – Hidden Treasure
As if to offset the two disadvantages just described, the player who goes Riichi is awarded a privilege.
If you remember, after the wall was broken at the beginning of the game a tile in the wall was turned over (Mekuri-pai). During the course of the game several more tiles may be turned over next to the first Mekuri-pai. They serve as extra Mekuri-pai, each one indicating an additional bonus tile. When a player completes his hand without going Riichi he may claim any Bonus tiles that are in his hand as indicated by each Mekuri-hai.
However, when a player goes Riichi he may also check each of the tiles beneath the Mekuri-pai. He may look at these hidden tiles at any time after going Riichi to see whether his hand contains any extra Dora.
Thus, if there are two Mekuri-pai in the wall, a player who goes Riichi may also check the two tiles beneath them to calculate the number of Dora in his hand. This gives him a chance to improve his final score.
Going Riichi to Improve Your Score
As has been said, a player with a Yaku in his hand can go Ron without having to go Riichi. However, a player with Yaku in his hand may elect to go Riichi in the hope of further improving his score.
Firstly, by going Riichi the player increases his scoring potential by one point. (Riichi is counted as 1 Yaku.)
Secondly, going Riichi gives the player the right to check for extra Dora from the tiles secreted beneath the exposed Dora-indicator tiles. If several tiles in the wall have been exposed in the course of play, the chances of gleaning extra Dora points from the tiles hidden beneath them is greatly increased.
Two Players Go Ron on the Same Discarded Tile
You can play this in two ways. The first option is the more usual:
- Both players are paid by the one who gave away the tile. In this case, if the Oya completed his hand he remains Oya. If only one of the players went Riichi the Riichi-tenbo goes to the player who is next in sequence (anticlockwise) to the Oya.or
- Only the player who is next in sequence (anticlockwise) to the one who gave away the tile can claim it.