Rinshan Kaihou (After a Kan)

Declared on a closed tenpai hand by discarding sideways and betting 1000 points. Locks the hand and unlocks a chance for ippatsu and uradora.

Winning within one go-around after declaring riichi, before any call or kan interrupts the turn. Closed-only by virtue of requiring riichi, and one of the cheapest ways to add a free han to a riichi hand — it stacks freely with everything else riichi unlocks.

Winning by self-draw on a fully closed hand (no calls). The default kicker on any closed tsumo win, which is why riichi + pinfu + tsumo is the canonical fast-cheap closed-attack template.