Oya

The oya 「親」 (lit. parent), known in English as the dealer, is the player in the East seat. The dealer gets special benefits when winning a hand.

Rule overview

Dealers have the following properties:

• The dealer is always the East seat. This means the dealer always gets the first draw, which is a slight increase to hand speed.
• A dealer's winning hands are worth +50% more (or about +50%, due to rounding).
• Dealers can renchan. When a dealer wins the hand, or when tenpai at exhaustive draw, the wind seating does not rotate. This extends the game by an extra hand.
• Dealers pay x2 as much when another player wins via tsumo. (They do not pay more when dealing in.)

The current dealer is denoted by using the dealer marker. Alternatively, the dealer marker notes the original dealer, and some other method is used to mark the current dealer.

Dealer rotation

During the course of the game, the dealer seat rotates among the four players. Seats rotate when:

1. A player other than the dealer wins a hand.
2. The dealer fails to attain tenpai at exhaustive draw.

Conversely, if a dealer wins, or is in tenpai at exhaustive draw, then the seats do not rotate. Each time this happens, the game length is extended by 1 extra hand.

Once every player gets to be a dealer once, the round wind changes. In a hanchan, everyone gets 2 chances at the dealer seat.

Some rulesets only enable renchan if the dealer wins, meaning that seats rotate when the dealer is tenpai at exhaustive draw.

Strategy

Being the dealer is mostly beneficial. It is better to win as the dealer than not, due to the +50% score bonus and the ability to renchan (an extra hand, while retaining dealership).

However, being the dealer is not always helpful:

• When a dealer has a large lead near the end of the game, they should avoid winning to avoid extending the game. Each renchan gives the other players a chance to build a yakuman and comeback.
• When another player wins by tsumo, the dealer has to pay more. The extra points lost from tsumo can be significant during close games or with big hands.

Rule variations

Renchan

There are two main rule variations regarding the dealer's renchan:

Renchan conditions:

• Agari renchan: The dealer only renchans after a win.
• Tenpai renchan: The dealer renchans after a win, or if tenpai at exhaustive draw.

Agariyame: In the last round, dealers may or may not be allowed to decline a renchan.

• Some rules let the last dealer choose to end the game when they win the hand.
• Other rules end the game when a 1st-place dealer wins, regardless of whenever they want to or not.
• Other rules do not let the dealer to end the game. The game ends when the dealer does not win.

Tiebreakers

When players are tied at the end of the game, some rulesets break the tie based on initial dealership. In order of priority, 1st dealer (East player in East 1) > 2nd dealer (South player in East 1) > 3rd dealer (West player in East 1) > 4th dealer (North player in East 1). This order is used because, traditionally, being the last dealer is seen as an advantage. The last dealer can end the game as soon as they reach first place in the last round; other players do not have this luxury.