1. Riichi as a Rule
Definition
Declare Riichi when your hand is closed and in tenpai.
Say “Riichi”, discard a tile sideways, then place a 1,000-point stick on the table.
After declaration
- Cannot: change your hand / Chi / Pon / open Kan
- Can: Tsumo / Ron / concealed Kan (under WRC conditions)
- Your hand becomes fixed: you must discard the tile you draw (tsumo-giri only)
Effects
- Enables Ippatsu (if no calls or Kans occur before your next discard)
- Enables Ura-dora (only when you win)
- Reveals to others that you are in tenpai
Special rules
- Riichi with fewer than 1,000 points = allowed
- Furiten Riichi = allowed
- Riichi with fewer than four tiles left in the live wall = allowed
2. Riichi as a Yaku
Han: 1 han
Closed only
Difficulty: ★☆☆☆☆
Requirement
Win after declaring Riichi.
Meaning
Basic closed-hand yaku that unlocks ura-dora and ippatsu.
Good with
Pinfu / Tanyao / Iipeikou / Dora-heavy hands
Cannot combine
Open hands / does not stack with Double Riichi