Keishiki tenpai
Keishiki tenpai 「形式聴牌」, also known as keitan or shaped tenpai, is a tenpai hand with no yaku. Such a hand cannot win normally, but can still win points for tenpai settlements at ryuukyoku. It can also win if it gains a conditional yaku, namely haitei, houtei, rinshan, or chankan, but all of those are rare.
Strategy
Players do not necessarily aim for keishiki tenpai until late into the hand. Usually, consideration for such action begins on the third row of discards.
Even if the point gain/loss for being noten is relatively small, it can still matter when it comes to placement. When players are close in points, especially near the end of the game, the +1500 points or so can make a difference in placement. Also, there's a small chance that haitei or houtei will let you win the hand. Therefore, if pushing for keitan is safe, it can be reasonable.
However, players must be wary of other players already in tenpai, so defense considerations are important. It is better to lose points via noten than to deal into a big hand.
Rule variation
Some house rules do not allow a keishiki tenpai to receive tenpai payment; the hand is treated as noten due to lacking a yaku. However, this practice is generally uncommon.
External links
- Keishiki tenpai in Japanese Wikipedia