hand structure riichi

Sanankou

三暗刻

(さんあんこう)

Definition

Three concealed triplets - a 2-han yaku where you have three concealed triplets. One step below the yakuman suuankou.

刻子

Three identical tiles. Can be concealed (ankou) or open (minkou). Also called koutsu.

四暗刻

Four concealed triplets - a yakuman where all four melds are concealed triplets. Must win by tsumo or with a tanki wait on ron.