Proto-mahjong › Chinese classical › Babcock rules › Twenty Point Mah Jong
Twenty Point Mah Jong
R.F. Foster, 1924
Cross-comparison
corroborated — two or more independent sources agree on the facts that define this variant
| Source | Tiles | Hand | Flowers | Scoring | Payout |
|---|---|---|---|---|---|
| [1] | 144 (the standard 136 plus 8 flowers) | 13, out on 14 | used in the hand to form sets | all sets earn points; the hand cannot go out until points reach at least 20; points can be doubled | all players earn points |
- [1] designed in 1924 by R.F. Foster to solve the Chinese Classical problem of high-scoring hands thwarted by cheap wins and frequent wall-building
Reading it
1924, R.F. Foster, and the 20-point minimum that gives the game its name all confirm the chart. Sloperama adds the motive and the verdict: Foster's attempt satisfied nobody but paved the way for American mah-jongg in the 1930s, which supports the chart's placement of it beside the American line rather than in it.
Sources
Sloper, Tom. "FAQ 2b: Identifying a Mah-Jongg Variant." Sloperama. canonical checked 2026-09-18
Tile counts, hand sizes, flower handling and scoring for roughly 50 named variants. Primary source for most leaf nodes in this chart.
https://www.sloperama.com/mjfaq/mjfaq02b.html
Also cited on: Chinese archaic, Chinese pre-classical, Chinese classical, Shanghai / Hong Kong new style, Hong Kong old style, Modern HKOS and 43 more · bibliography #1