Seisan十三

Seisan (十三, "Thirteen") is one of the oldest kata in Okinawan karate. In the Kyan lineage it comes from the Shuri-te of Sokon Matsumura, from whom Kyan learned it, and it is regarded as the first major kata of the Sukunaihayashi (Kyan) line.

Seisan is a powerful form built on rapid shifts between shiko-dachi and zenkutsu-dachi to generate power, with long-range thrusting and kicking combinations. The "13" of its name has many folk interpretations (13 hands, 13 steps, etc.), none with firm historical basis. Known in Shotokan as Hangetsu (半月) and in Wado-ryu as Seishan.