Agon was a member of an unknown school who was hired along with Hakuryuu and a third nameless axeman by Fujibayashi Saizou to kill Naoyoshi Washitzu between the first and second rounds of the Tournament.
Agon is a large, brutish man with an intimidating look, shaggy chin-length black hair and for some reason blank eyes. He wears a simple black kimono with white borders and very large sleeves, white pants, and black shoes.
Not much of his personality is shown, but Agon seems to be a silent, stoic brute who relies on his strength. He only shows visible surprise when Zenmaru smash his axe.
Agon is first seen with Hakuryuu, the nameless member and Saizou in an alley, as the ninja spots Naoyoshi. Agon attacks Naoyoshi from behind with a katana, but because of his slow, brutish movements he only succeds in wounding him. As Shinnojo and Zenmaru arrives, he drops the sword and reveals his true weapons. While his partner Hakuryuu is defeated by Shin, Agon bellows and throws his axe at Zenmaru, who manages to break it to pieces with Hibashira. A stupefied Agon is then rushed by Zenmaru who cuts him down.
Like Hakuryuu and possibly the third assassin, Agon practices axemanship, wielding two elaborated axes at once, ususally hidden in his sleeves. Thanks to the weight and width of his weapons his attacks are difficult to stop with swords.
Unnammed Ax: Agon uses a tomahawk, that can be thrown at the opponent. Zenmaru was able to destroy one of his axes when it was thrown at him.
Despite being set during the Edo period in Japan, Agon's weapon is named after a native american weapon, a culture which japanese didn't know yet.