Gyakuten

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Discarded winning tile may not be enough for gyakuten.

Gyakuten 「逆転」 ("comeback") is when a player improves their placement during the last hand.

Knowledge of the points table is particularly helpful for pulling a comeback: it can help determine the needed tile composition, if you can open the hand, if you need to call riichi, and other key decisions. In any case, like most things in mahjong, at least a little luck is required to win.

Strategy for oorasu

The term "gyakuten" normally applies to a placement shift in the last hand of the game. In the last round, once a non-dealer wins, the game ends, and placement is finalized. Therefore, even a 100 point difference can matter. Lower players must develop a hand that gives enough score to pass the higher ranked players. On the other hand, players with their desired standing must find a way to retain their position at the end of the game, either by winning the final hand or simply avoiding losing points.

Gyakuten is important because placement is itself important. Thanks to oka and/or uma, a player can receive a large bonus for rising up a placement, or conversely, lose a lot by falling down a place. In some types of play, such as certain tournaments or tenhou.net's dan ranking, final placement is the only thing that matters.

Riichi

If an open version of a hand is enough to improve your placement, no matter how it's won, then open the hand for the extra speed. Similarly, if you can guarantee improvement with a damaten hand, then do that.

Riichi gives 1 han, plus random bonuses via ippatsu, ura dora, and/or mentsumo. If you're particularly lucky, a riichi-only hand can turn into 7900 points with riichi ippatsu mentsumo dora 1. Ideally, you should try to guarantee a comeback without any bonus han. However, if you have no reasonable way to do so, go for a riichi and hope you get enough points. At the same time, your opponents will be especially wary of a riichi in the last round, precisely because they don't want to lower their placement.

In some niche cases, the 1000 point riichi bet is enough to drop you down placement. If you have another yaku, you should usually go dama. If you don't have a yaku, then riichi is still worthwhile if you have a good wait. Since the trailing player is only 1000 points behind, any win they make would be enough for you to drop down, so you should still try to win.

Ties

When two players' scores are tied at the end of the game, there are two major rule variations on how the scores are treated:

  • Ties are broken based on the initial wind seating (seats in the first hand). The initial East player beats South beats West beats North.
  • Tied players split oka/uma bonuses evenly between tied players.

You should take note of which rule is used before playing. If ties are broken by wind seating, the player further from initial east player need to gain points to overcome the tie.

Score differences

In the last hand of the game, players are likely to only have one chance to win. Therefore, awareness of the point differences and the scoring table are key.

The following table displays the minimum han/fu value required to surpass a leading player that is 'X' points ahead of you. Note that:

  • "Direct hit" rons (a ron on the player you're trying to surpass) are worth double the value of "non-direct hit" rons.
  • Tsumo requires less points than a non-direct hit ron, because with tsumo, you take points from everyone. (E.g. if you tsumo with a mangan, you gain 8000 points, and the opponents lose 2000 points, allowing you to overcome a 10000 point gap.)
  • You should also account for honba and riichi bets when calculating score.
    • Each honba stick lets you surpass a +400 point lead for tsumo, a +300 point lead for ron, and a +600 point lead for direct hit ron.
    • Each riichi bet let you surpass a +1000 point lead regardless of how you win.
Gyakuten table
Han-Fu Non-dealer Dealer
Tsumo Ron Tsumo Ron
Non-dealer diff Dealer diff Non-direct hit Direct hit Non-direct hit Direct hit
1-30 1400 1600 1000 2000 2000 1500 3000
1-40 & 2-20 1900 2000 1300 2600 2800 2000 4000
1-50 & 2-25 2000 2400 1600 3200 3200 2400 4800
1-60 & 2-30 2500 3000 2000 4000 4000 2900 5800
1-70 3000 3600 2300 4600 4800 3400 6800
1-80 & 2-40 & 3-20 3400 4000 2600 5200 5200 3900 7800
2-50 & 3-25 4000 4800 3200 6400 6400 4800 9600
2-60 & 3-30 5000 6000 3900 7800 8000 5800 11600
2-70 5900 7000 4500 9000 9200 6800 13600
2-80 & 3-40 & 4-20 6500 7800 5200 10400 10400 7700 15400
3-50 & 4-25 8000 9600 6400 12800 12800 9600 19200
3-60 & 4-30 9900 11800 7700 15400 15600 11600 23200
Mangan 10000 12000 8000 16000 16000 12000 24000
Haneman 15000 18000 12000 24000 24000 18000 36000
Baiman 20000 24000 16000 32000 32000 24000 48000
Sanbaiman 30000 36000 24000 48000 48000 36000 72000
Yakuman 40000 48000 32000 64000 64000 48000 96000

External links