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EMA vs WMO

All Categories Athletics Board Games Combat Sports Equestrian Esports Individual Sports Motor Sports Party Games Playground Games Racquet Sports Team Sports Tile Games Water Sports Winter Sports All Categories Athletics Board Games Combat Sports Equestrian Esports Individual Sports Motor Sports Party Games Playground Games Racquet Sports Team Sports Tile Games Water Sports Winter Sports

All Categories Athletics Board Games Combat Sports Equestrian Esports Individual Sports Motor Sports Party Games Playground Games Racquet Sports Team Sports Tile Games Water Sports Winter Sports

AFirst Sport

🏅

EMA

Mahjong (Riichi)

First Sport

Details

Players4

Setting-

SeasonEMA Riichi Rules, 2025 edition (August 2025; supersedes the 2016 edition)

CategoryTile Games

BSecond Sport

🏅

WMO

Mahjong (MCR)

Second Sport

Details

Players4

Setting-

SeasonMahjong Competition Rules, 2014 English edition (11 April 2014; supersedes the 2006 Green Book)

CategoryTile Games

6

Shared Topics

6

Different Rules

0

Shared Rules

Rule-by-Rule Comparison(6)

2. Components

Different

EMA

There are 34 basic tile types. A full set contains four identical tiles of each type, giving 136 tiles in play (1, 1.3); Three suits — circles (pinzu), bamboo (sōzu) and characters (manzu) — each numbered one to nine (1.1); The ones and nines of each suit are called terminals (1.1)

WMO

Honor tiles are the winds and dragons taken together. There are four Wind Tiles — East, South, West, North — and three Dragon Tiles — White, Red and Green — with four of each (3.4.15); Terminal tiles are the ones and nines of a suit, together with the honor tiles (3.4.16); Flower tiles are used: ...

3. Setup

Different

EMA

Four players, each associated with a seat wind. East is the starting player; South sits at East's right, West across from East, North at East's left (2.1); The counter-clockwise order east-south-west-north does not correspond to compass directions (2.1); Over a full game each player is East at le...

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WMO

Four players per table, each table playing as an independent group (3.5.2); Seating is the placement of players around the table by table number, determined by drawing lots or arranged in advance under the tournament regulations (3.4.7); Lots are drawn publicly, fairly and impartially; where a te...

4. Gameplay

Different

EMA

A full game is two rounds — the east round and the south round — each of at least four hands, during which each player is East in turn (3.1); A hand ends when a player declares a win or an exhaustive draw occurs (3.1, 3.4); A turn begins when a player draws from the wall or claims a set, and ends...

WMO

Every claim on a discard must be verbalized (3.6.1); Say "Chi" to chow, "Pung" to pung, "Kong" (or "Gang") to kong, "Hu" to declare mahjong, and "Hua" when taking a flower replacement (3.6.1); Players must not call out the names of tiles when discarding, and are forbidden to discuss, gossip, or c...

5. Scoring & Winning

Different

EMA

All players are responsible for each hand being scored correctly and to the maximum; each player counts their own han and minipoints and others must correct mistakes (4.1); Count han first — the yaku (at least one) plus dora, kan dora, and ura dora. Ura dora count only for a riichi hand, and a ti...

WMO

Three conditions must all hold to declare "Hu": the hand is one of the permissible structures; its fan total at least 8 points; and the winning tile was obtained by a permitted method (3.9.1); The eight-point minimum is the defining constraint of MCR — a structurally complete hand that scores les...

6. Variants & House Rules

Different

EMA

Riichi is one of several mahjong rule families and is clearly distinct from the others, though all share the same core: build four sets and a pair from tiles; Mahjong Competition Rules (MCR) is the other major competitive rule set. Its current text is the World Mahjong Organization's 2014 English...

WMO

MCR and riichi are the two major competitive mahjong rule sets and are scored on entirely different principles: MCR counts fan against an eight-point threshold (3.8, 3.9.1), while riichi counts han and minipoints and has no equivalent minimum; MCR uses flower tiles and flower replacement (3.4.20)...

Declaring a Win

Different

EMA

Tsumo — winning on the tile just drawn, by clearly calling "tsumo". A furiten player may still call tsumo (3.3.11); Ron — winning on the most recently discarded tile, by clearly calling "ron", unless furiten (3.3.12); Robbing a quad — the tile added to an extended quad may be claimed for a win wi...

WMO

Winning (hu) is reached when, after taking a discard or drawing, the fourteen tiles form a complete structure as prescribed and the hand scores eight or more points (3.4.22); Self-drawn — winning on a fresh tile taken from the wall (3.4.23); A hand that reaches neither a declaration nor a winner ...

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