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Mahjong Master
advanced Yakuman Very Rare

Tsuuiisou

字一色 | Tsuuiisou

Build your entire hand using only honor tiles -- winds and dragons -- with no suited number tiles at all.

By Kenji Tanaka · Updated

Overview

Tsuuiisou, all honors, is a yakuman in which every tile in your hand is an honor, made up only of winds and dragons with no numbered suit tiles at all. Because honors form only triplets and pairs, a tsuuiisou hand is necessarily all triplets (or quads) plus an honor pair, so it overlaps with toitoi and frequently with the dragon and wind yakuman: a tsuuiisou can simultaneously be daisangen or daisuushii, stacking yakuman for a huge score. A seven-pairs hand made entirely of honor pairs also qualifies as tsuuiisou in rule sets that allow it. Assembling the hand requires drawing and calling many honor tiles, each limited to four copies, so it usually grows from a start unusually rich in winds and dragons. Opponents read the threat quickly as honor triplets pile up. Tsuuiisou rewards committing early to an all-honor plan when the tiles cooperate, and it is one of the more spectacular yakuman to complete.

Han Value
Yakuman

Example Hand

111z 333z 555z 777z 6z 6z

Conditions

  • Every tile in the hand must be an honor tile (winds: 1z-4z, or dragons: 5z-7z)
  • No suited tiles (characters, circles, or bamboo) are allowed
  • The hand can be open — calling pon on honor tiles is allowed
  • The hand will necessarily be all triplets (or kans) plus a pair, since sequences cannot be formed with honor tiles
  • Tsuuiisou inherently overlaps with toitoi and multiple yakuhai, but the yakuman value supersedes all other han

Strategy Tips

  • There are only seven types of honor tiles (four winds and three dragons) with four copies each, giving 28 total honor tiles in the game. You need 14 of them for your hand, which means you need half of all honor tiles in play — a very tall order.
  • If your starting hand has four or more honor pairs or triplets, tsuuiisou becomes a real possibility. The key is drawing or calling enough honors before other players snap them up for their own yakuhai melds.
  • Tsuuiisou often overlaps with shousuushii or daisangen. If you fall short of collecting all the wind or dragon triplets you need, check whether your hand qualifies for one of those yakuman instead.