Dora

Riichi mahjong features dora tiles. Dora is a property that tiles may possess that increase a hand's value by simply having them. A tile possessing dora is called a dora tile, or simply dora. One dora equals one han for scoring. However, the possession of dora does not count as yaku. In other words, it is possible for a complete hand to possess dora and still remain invalid. Thus, the hand may actually be worth nothing. In contrast, it is possible for a hand composed of just one low ranking yaku to be very valuable just by having a large number of doras. Therefore, dora should influence a player's decision making process, but not to the extent of neglecting yaku. Furthermore, the luck element of hidden doras revealed by ura dora and/or kan dora indicator tiles wields an even greater influence on the game.

Dora indicators
Dora tiles are indicated by revealed tiles in the dead-wall. The dead-wall contains ten dora indicator tiles. At the start of a hand, the first of these ten tiles is revealed. Given the dora indicator, the next tile in the suit following the dora indicator has a dora. For suited tiles, if the dora indicator is a 9, then the order loops around and the 1 is a dora. The same applies to the wind and dragon order.

Wind order: >  >   >   >

Dragon order: > >  >

For example, with the following dora indicators:
 * Indicator: . Dora:
 * Indicator: . Dora:

Examples of the indicator as the honor tiles:
 * Indicator: . Dora:
 * Indicator: . Dora:

Examples of the indicator as the "end":
 * Indicator: . Dora:
 * Indicator: . Dora:
 * Indicator: . Dora:

Red five dora
In addition, Saki tournament games include red-five dora tiles. These automatically count as dora, regardless of the dora indicator.

Red-five dora tiles:

Multiple dora per tile
While there is usually only one revealed dora indicator tile, there can be as many as ten if four kan are revealed a riichi declarer wins. If dora indicator tiles repeat, then indicated tiles will have multiple dora. If the dora indicator is a 4, then the red-five tiles will have multiple dora. The very rare maximum dora count for a single tile is 5.

Dora strategies
A single dora can double the value of a winning hand and mutiple doras dramatically increase a hand's score. Like with the regular rules of hand composition, a dora tile must be part of composition in terms of melds and waits. Otherwise, a hand possessing dora that does not constitute a legal winning hand is worth zero. Therefore, it may but not always be advantageous to have doras in a hand. Overall, possession or discarding of dora tiles depends on the hand's development, which may or may not need them. Dora tiles may be dangerous to discard late in the round; a careful balance between keeping isolated dora for potential use and getting rid of them before it's too late is essential.