Chinroutou

Chinrotou (清老頭) is a yakuman, where every tile is a terminal, i.e., a one or a nine.

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 chiitoitsu variation.