Chinroutou

Chinrotou (清老頭) is a yakuman, where every tile is composed of terminals (1s and 9s).

Tile pattern

Agari: or

Formulation

For this yakuman, there are only six types of terminals available: two from each of the numbered suit (1 and 9). Given the basic hand pattern of four melds and a pair, five out of the six types of terminals are needed to build this hand. Since there are only six tile types available for this hand, it is impossible to form a chii toitsu variation.