How to play

You can play WCOOM® on following  Mahjong Sites:


Dora Mahjong

Dragon Kong


Do you want to win the World Championship of Online Mahjong.

To play WCOOM2013 you have to buy in directly to the Online Main Event Final. If you do not have a player account with one of our partner above please sign up and register for WCOOM2013. All players can join no qualification or invite is needed to play, just register now.


Tournament info

WCOOM® Riichi Main Event Final Information

Date Sunday 8 December, CET: 14:00 JAPAN: 22:00
Rules: Japanese Riichi
Format: Shootout, 2 players per table go through to the next round, 4 hands is played per round.
Buy in $30
Fee $3
Min players 4
Max players 2000
Prize Winner will become the Online World Champion, Money from the pot with extra 1000 USD and a VIP trip to Macau.
Payout structure for the money pot Normal payout structure for the money pot. See tournament lobby when you register.


The tournaments will be played in shootout format. Each tournament is divided in to successive rounds. The top of the two ranked players on each table will progress to the next round while the other players are eliminated from the tournament. As the rounds progress, the number of remaining players and the tables decrease, the final round consisting of the top four players who have made the final table. The winner of the final table in the Main event is the overall mahjong champion in that discipline.





Basic Premises

  • Flower and season tiles are not used.
  • Wind rotation after each hand except if East wins or is Tenpai.
  • It is possible to declare Riichi on any hidden hand that only needs one more tile to be a winning hand. 1000 points will be placed, as an extra bet by the player declaring Riichi and the game will play itself until somebody wins or there is a draw. The player who has declared Riichi may expand a pong to a kong if the right tile is drawn. If a player who has declared Riichi declines to go mahjong on a tile is still Riichi, but may then only declare Mahjong on a drawn (not discarded) tile. The winner of the hand takes the extra 1000 points. In case of a draw, the points will be transferred to the next hand.
  • A player will become Furiten if he or she needs a tile that he or she has already discarded to go Mahjong. A player who is Furiten may only declare Mahjong on a self-drawn tile. A player will stop being Furiten if he or she discards tile(s) so that the tile needed for Mahjong is no longer one that he or she has already discarded.
  • The game ends if a player goes below 0 points.
  • A player will be Tenpai if nobody wins and the player is only one tile away from a Mahjong hand.
  • Dora, Kan Dora and Ura Dora are used (see the Special Hands section for details).
  • Red fives are not used in any Riichi rule set on this site.
  • Washout can happen if all players discard the same wind in the first go-around; if four kongs are declared and nobody robs the last kong and the kongs are not declared by the same player; if all players declare Riichi

Going Mahjong

At least one yaku (fan) is required to go mahjong. See Special Hands below.

Note that losses are limited; a player cannot go below 0 points.

Special Hands

The following special hands score one or more yakus.

Yaku Patterns

Name Open Conc. Description
Riichi 1 Going out with mahjong after having declared Riichi. One extra yaku is awarded if you go out within the next uninterrupted go-around, inluding your next draw from the wall (Ippatsu). One extra yaku is awarded if riichi was declared in the very first uninterrupted go-around (Daburu riichi).
Fully Concealed Hand (Menzen Tsumo) 1 Going out on self-draw with a concealed hand.
All simples (Tanyaou Chuu) 1 2 A concealed hand consisting only of suit tiles 2-8. (Scores -/1 in EMA Riichi)
Pinfu 1 A hand that gives no minipoints beside those awarded for going out. The hand must consist of four chiis and a pair which is not in dragons, seat wind or prevalent wind, and the hand must be won on a two-sided wait.
Pure Double Chii (Iipeikou) 1 Two chiis of the same value and suit.
Mixed Triple Chii (San Shoku Doujun) 1 2 Three chiis of the same value, with one in each suit.
Pure Straight (Itsu) 1 2 Three consecutive chiis (1-9) in the same suit.
Dragon Pon (Fanpai/Yakuhai) 1 1 A pon or kan in dragons
Seat Wind (Fanpai/Yakuhai) 1 1 A pon or kan in the players wind.
Prevalent Wind (Fanpai/Yakuhai) 1 1 A pon or kan in the prevalent wind.
Outside Hand (Chanta) 1 2 A hand where all sets contain a terminal or honor tile, and at least one of the sets is a chii.
After a Kan (Rinchan Kaihou) 1 1 Going out on a replacement tile for a kan.
Robbing a Kan (Chan Kan) 1 1 Going out by robbing a kan (see ????)
Bottom of the Sea (Haitei) 1 1 Going out on the last tile of the live wall, or the discard thereafter.
Seven Pairs (Chii Toitsu) 2 A hand consisting of seven pairs. Note, that this is one of the two special hands that don’t follow the standard 4 sets plus 1 pair formula. It is also special in that you are awarded 25 points for going mahjong with a seven-pairs hand.
Triple Pon (San Shoku Dokou) 2 2 One pon or kan in each of the three suits, all having the same number.
Three Concealed Pons(San Ankou) 2 2 Three concealed pons or kans.
All Pons (Toi-toi hou) 2 2 A hand with four pons/kans and one pair.
Half Flush (Honitsu) 2 3 A hand with tiles from only one suit plus honor tiles.
Little Three Dragons (Shou Sangen) 4 4 Two pons/kans of dragons plus one pair of dragons. (No extra yakus are scored for the dragon pons individually.)
All Terminals and Honors (Honroutou) 2 2 A hand consisting of only terminals and honors.
Terminals in All Sets (Junchan Taiyai) 2 3 A hand with atleast one chii and where all sets contains terminals.
Twice Pure Double Chiis (Ryan Peikou) 3 Two pair of chiis, where each pair consists of two identical chiis.
Full flush (Chinitsu) 5 6 A hand with tile from only one suit and no honor tiles.

Yakuman Patterns

Yakuman hands are all treated as 13+ yakus in terms of scoring.

Thirteen Orphans (Koku Shimusou) One of each honor tile and terminal plus a fourteenth tile forming a pair with one of thos
Nine Gates (Chuuren Pooto) A hand consisting of the tiles 1112345678999 in one suit plus one extra tile in the same
Blessing of Heaven (Tenho) East wins on the initial hand.
Blessing of Earth (Chiho) A hand won on self draw in the first go-around.
Blessing of Man (Renho) A hand won on discard in the first go-around. Only possible in EMA Riichi.
Four Concealed Pungs (Suu Ankou) Four concealed pons or kans.
Four Kans (Suu Kan Tsu) Four kans.
All Green (Ryuu Iisou) A hand consisting of only green tiles, i.e., green dragons and bamboo 2, 3, 4, 6 and 8.
All Terminals (Chinrouto) A hand consisting of only terminal tiles.
All Honors (Tsuu Iisou) A hand consisting of only honor tiles.
Big Three Dragons (Dai Sangen) A pon or kan in each of the three dragons.
Little Four Winds (Shou Suushi) A pon or kan in three of the winds and a pair in the fourth wind.
Big Four Winds (Dai Suushii) A pon or kan in each of the four winds.

Dora, Kan Dora and Ura Dora

The face-up tile in the wall is the Dora indicator. The next tile in sequence is the Dora. So if the Dora indicator is Bamboo 2, the Dora is Bamboo 3, if the indicator is Character 9, the Dora is Character 1. If the Dora indicator is a dragon or a wind, the following sequences are used: the dragon sequence is Red, White, Green; the wind sequence is East, South, West, North.

For each Dora tile a player has in a winning hand, one additional yaku is awarded. Only having a Dora tile in ones hand does not make the hand qualify for Mahjong, however.

If a Kan is declared, another tile is turned face up, indicating another Dora tile (a Kan Dora).

If a player has declared Riichi and goes Mahjong, the tile beneath each Dora indicator is exposed. The newly exposed tile(s) indicate Ura Dora(s) which work just like Dora tiles.


The final score of a hand is complicated to calculate by hand, so it is presented in the form of tables here. If the winner has less than 5 yaku, minipoints need to be calculated first.

Combination Minpoints if open Minipoints if concealed
Pong of simples 2 4
Pong of terminals/honors 4 8
Kon of simples 8 16
Kon of terminals/honours 16 32


Combination Minpoints
Pair of dragons 2
Pair of seat wind 2
Pair of prevalent wind 2
Edge wait, closed wait or pair wait 2
Self-draw except with pinfu hand 2
Open pinfu 2
Wining with concealed hand 30
Seven pairs (not cumulative) 25
Open hand/self draw 20

Based on the number of minipoints and yakus in the player’s hand, losers shall pay the points to the winner according to the below tables:

Winner is East and wins on self draw (Tsumo)
Minipoints 1 yaku 2 yaku 3 yaku 4 yaku
20 700 1300 2600
25 1600 3200
30 500 1000 2000 3900
40 700 1300 2600 4000
50 800 1600 3200 4000
60 1000 2000 3900 4000
70 1200 2300 4000 4000
80 1300 2600 4000 4000
90 1500 2900 4000 4000
100 1600 3200 4000 4000


Winner is East and wins on discard (Ron)
Minipoints 1 yaku 2 yaku 3 yaku 4 yaku
25 2400 4800 9600
30 1500 2900 5800 11600
40 2000 3900 7700 12000
50 2400 4800 9600 12000
60 2900 5800 11600 12000
70 3400 6800 12000 12000
80 3900 7700 12000 12000
90 4400 8700 12000 12000
100 4800 9600 12000 12000


Winner is any wind except East and wins on self draw (S,W,N/East) (Tsumo)
Minipoints 1 yaku 2 yaku 3 yaku 4 yaku
20 400/700 700/1300 1300/2600
25 800/1600 1600/3200
30 300/500 500/1000 1000/2000 2000/3900
40 400/700 700/1300 1300/2600 2000/4000
50 400/800 800/1600 1600/3200 2000/4000
60 500/1000 1000/2000 2000/3900 2000/4000
70 600/1200 1200/2300 2000/4000 2000/4000
80 700/1300 1300/2600 2000/4000 2000/4000
90 800/1500 1500/2900 2000/4000 2000/4000
100 800/1600 1600/3200 2000/4000 2000/4000


Winner is any wind except East and wins on discard (Ron)
Minipoints 1 yaku 2 yaku 3 yaku 4 yaku
25 1600 3200 6400
30 1000 2000 3900 7700
40 1300 2600 5200 8000
50 1600 3200 6400 8000
60 2000 3900 7700 8000
70 2300 4500 8000 8000
80 2600 5200 8000 8000
90 2900 5800 8000 8000
100 3200 6400 8000 8000

If the winner has more than 5 yaku, losers pay as follows:

Limit hands
Hand Yaku East Wins Other Wind Wins (S,W,N/East)
Mangan 5 4000 2000/4000
Haneman 6-7 6000 3000/6000
Baiman 8-10 8000 4000/8000
Sanbaiman 11-12 12000 6000/12000
Yakuman 13+ 16000 8000/16000