A self-proclaimed genius, Amiba trained in Nanto Suichō Ken under Rofū, but never finished. Amiba is jealous of Toki, and bears a grudge against Toki because Toki once scolded him when Amiba was recklessly trying to "heal" an old man (by randomly pressing a painful point on the old man's injured leg).
Amiba later teamed up with Jagi, who helped make Amiba resemble Toki and even scarring his back with a club to match Toki's scar. Amiba had picked up enough Hokuto Shin Ken techniques from Jagi to successfully impersonate Toki.
He is known for his sadistic "new pressure point test" on living humans and reports his findings to Raoh. He also claims that he can learn any martial art under short period. He develops a style imitating Hokuto Shinken, which he names Hokuda Shin Ken (北蛇鍼拳, "Needle Fist of the North Snake") in Ten no Haō. Kenshiro finally used Zankai Sekihoken, making Amiba walk towards his death in a high rise building.
