Ryantan
Ryantan 「リャンタン」, kantan, and pentan 「ペンタン」 are a group of complex waits that can wait to complete either a pair or a sequence. They appear as a triplet with a nearby adjacent tile:
- Ryantan (ryanmen + tanki): Appears as a triplet with a tile adjacent, where none of these tiles are terminals. Example: 2223, which can be treated as 22 + 23 (ryanmen) or 222 + 3 (tanki).
- Kantan (kanchan + tanki): Appears as a triplet with a tile numerically 2 apart. Example: 2224, which can be treated as 222 + 24 (kanchan) or 222 + 4 (tanki).
- Pentan (penchan + tanki): Appears as a triplet with a tile adjacent, where either the triplet or adjacent tile are composed of terminals. Examples: 1112, which can be treated as 111 + 12 (penchan) or 111 + 2 (tanki).
| Kanji |
リャンタン ペンタン |
|---|---|
| Fu | Dependent |
| Tile types waiting | 3 or 2 sided wait |
| Tiles available | 11 or 7 tiles |
| Pattern example |
      |
In order to enter tenpai with any of these waits, the hand must not have any other pairs. If it already has a "stable" pair, the adjacent tile can be treated as a floating tile.
Pattern
Ryantan
Waiting for: , ,
Note: this hand will score pinfu if won on or . If won on the , the hand will have a triplet, thus invalidating the yaku.
Kantan
Waiting for: 
or
Pentan
Waiting for: ,
Waiting for: 
,
Tatsumaki
Tatsumaki can be viewed as two ryantan waits fused together. It consists of two triplets that are 2 ranks apart, and one floating tile between the triplets.
Waiting for: 
Note: when this pattern wins on either triplet tile (in this example, or ), the hand can complete a shanpon wait instead of a ryanmen wait. This can be important as the shanpon wait gives more fu, and possibly gives sanankou.
Value
Kantan and pentan are always worth 2 fu, so they cannot be used for pinfu. Completing the tanki is worth more fu, since it forms a triplet.
Ryantan is worth fu only if it completes the tanki portion. If it completes the ryanmen, no fu is scored, so it can be used for pinfu. E.g. a hand with a 4445 wait can score pinfu when winning with 3 or 6, but not with the 5.