Iipeiko and Ryanpeikou Yaku: Twin Sequences
Sep 22, 2026 · 4 min read
Iipeiko ("one set of identical sequences") forms when you have TWO sequences that are exactly identical within the same suit, for example 2-3-4 Characters twice. It's worth 1 han, but ONLY applies to closed hands -- it disappears entirely if your hand is open.
Ryanpeikou: Double the Iipeiko
Ryanpeikou forms when you have TWO SEPARATE pairs of identical sequences at once (so all 4 sets are two pairs of twin sequences). This replaces Iipeiko outright (not counted twice) and is worth 3 han, closed hand only.
Why It's Rare
Iipeiko needs the luck of drawing 6 identical tiles for 2 twin sequences, so it's rarely planned from the start -- it usually only becomes visible once your hand is nearly complete.
An example Iipeiko hand -- the 2-3-4 Characters sequence appears exactly twice, the rest is free.
Check another yaku that also only works closed.
Read About Pinfu →