What are the variants & house rules in Mahjong (MCR)?

6. Variants & House Rules

MCR Compared with Riichi

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); riichi sets them aside entirely
Both are recognised rule sets of the Mahjong International League

Which Edition Applies

This summary follows the WMO 2014 English edition, the current text from the body that makes the rules
The European Mahjong Association continues to name the 2006 "Green Book" as the reference for its MERS ranking tournaments, alongside its own Tournament Regulations and Referee Manual, official for MERS events since 1 January 2009. A European tournament may therefore be run under the older text
Where the two differ, check the tournament's own announcement — the organiser states which edition governs

Competition Formats

Events may be Individual, Team or Group Ranking (3.5.3)
Three competition methods exist — Elimination, Round Robin and Mixed — and a tournament may use one and only one of them (3.5.4)

6. Variants & House Rules

MCR Compared with Riichi

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); riichi sets them aside entirely

Both are recognised rule sets of the Mahjong International League

Which Edition Applies

This summary follows the WMO 2014 English edition, the current text from the body that makes the rules

The European Mahjong Association continues to name the 2006 "Green Book" as the reference for its MERS ranking tournaments, alongside its own Tournament Regulations and Referee Manual, official for MERS events since 1 January 2009. A European tournament may therefore be run under the older text

Where the two differ, check the tournament's own announcement — the organiser states which edition governs

Competition Formats

Events may be Individual, Team or Group Ranking (3.5.3)

Three competition methods exist — Elimination, Round Robin and Mixed — and a tournament may use one and only one of them (3.5.4)

6. Variants & House Rules