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Ippatsu (一発)

1 han

Win within one turn after declaring riichi without any calls.

How Ippatsu (一発) works

A bonus for winning within one go-around immediately after declaring riichi, before your next draw, with no intervening calls.

After you declare riichi, ippatsu applies if you win — by draw or discard — on or before your very next turn. The window is broken if any player calls pon, chi, or kan in between, since a call interrupts the natural flow of turns. It can only attach to a riichi hand and is one of the easiest luck-based bonuses to stack on top of riichi and other yaku.

Good to know
  • Requires riichi to have been declared; it cannot exist on its own.
  • Any call (pon, chi, kan) by any player during the window cancels it, including the winner's own kan.
  • The chance lapses once your next self-draw passes without a win.

Ippatsu (一発) — FAQ

Does ippatsu survive a kan?

No. A kan declared by anyone within the ippatsu window cancels it, since the kan interrupts the uninterrupted turn sequence.

Can I get ippatsu on a discard?

Yes. Winning by ron within the one-turn window after riichi qualifies, as long as no call occurred in between.

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