Seat and Round Importance

22.1 Dealer Advantage

The dealer (親, oya) has two major advantages: (1) they receive 50% more points when winning, and (2) they retain the dealer position if they win or are tenpai at a draw (renchan). These advantages compound—a dealer on a winning streak can accumulate a massive lead while opponents are powerless to rotate them out. Understanding dealer advantage is crucial for both playing as dealer (play more aggressively to exploit the bonus) and playing against the dealer (consider the cost-benefit of preventing their renchan).

22.2 Wind Round Dynamics

During the East round (東場), all four players will serve as dealer once (minimum). The East round is relatively "balanced" because everyone gets dealer advantage. During the South round (南場), the game is typically approaching its end, and point gaps established in the East round become more significant. Strategic adjustments between rounds are subtle but important: aggressive play to establish leads is more common in the East round, while defensive play to protect leads is more common in the South round.

22.3 Seat Wind Value

Your seat wind changes each hand, affecting which wind tiles are yakuhai for you. In the East round, the East player benefits most (double East = seat + round wind). In the South round, the South player has this double-wind advantage. Awareness of your current seat wind should influence how you evaluate wind tiles in your hand—a pair of your seat wind is more valuable than a pair of a guest wind.

22.4 Dealer Strategy in Detail

The dealer advantage in riichi mahjong is substantial and well-documented. Tenhou data shows that across large samples, the dealer wins approximately 25-28% of hands (vs ~20-22% for non-dealers), partly because the dealer draws first and partly because the 50% scoring bonus incentivizes aggressive play. Professional players like Moriyama Shigeru (森山茂和), former president of the Japan Professional Mahjong League, have written about "親の攻め" (oya no seme, "dealer's attack") as a fundamental strategic posture: when you are dealer, lean toward attacking because the reward-to-risk ratio favors you.

Specifically, a non-dealer mangan tsumo pays 2,000/4,000 (total 8,000). A dealer mangan tsumo pays 4,000 all (total 12,000). This 50% bonus means the dealer can justify riskier plays — the same push/fold calculation that says "fold" for a non-dealer might say "push" for the dealer, because the win value is 1.5× higher. This is particularly impactful for renchan situations where consecutive dealer wins can accumulate enormous point leads.