Curriculum · 18 / 50
Situational yaku: ippatsu, rinshan, chankan, haitei, and houtei
Ippatsu, rinshan kaihou, chankan, haitei on the last wall tile and houtei under the river: the timing yaku, their han, and the Tenhou exclusions.
The principle
Ippatsu adds 1 han to a win after riichi and before the declarer’s next discard, provided no tile call or kan occurred. Double riichi is worth 2 han when riichi is declared on the first discard before any call or ankan.
Rule and example
Rinshan kaihou is worth 1 han for tsumo on a kan replacement tile. Chankan is worth 1 han for ron on the tile used to promote a pon into an added kan.
What changes
Haitei is worth 1 han for tsumo on the last tile of the live wall. Houtei is worth 1 han for ron on the discard that follows that final draw.
Mistake to avoid
Under Tenhou rules, ippatsu does not combine with rinshan and haitei does not combine with rinshan. WRC 2025 adds renhou, a closed 5-han yaku for ron before a non-dealer’s first draw, with no other yaku or dora.
Rules references
- Tenhou rulesReference profile used for game mechanics and scoring.
- WRC Rules 2025International rules compared whenever their options differ from Tenhou.