Hattoryu is the fighting style of Hyouzou. He wields eight swords at once, one in each hand and one in each of his six tentacles. He is able to coat the swords in his blue-ring octopus venom to kill opponents with his attacks. After overdosing on Energy Steroids, he became powerful enough to cut through iron.
Chidoriashi Hash (千鳥足ハッシュ,Chidoriashi Hasshu?, literally meaning "Drunken Staggering Hash"): Hyouzou swings his eight swords against his opponents, one with each tentacle and two in his hands. This was first used while he was drunk, and under the influence of Energy Steroids, which led him to be strong enough to slash through many New Fish-Man Pirates members and cut through the Iron Shell Squad's shields with ease. In the Viz manga and FUNimation subs, this is called Tottering Hash.
Modoku no Ken (猛毒の剣,Mōdoku no Ken?, literally meaning "Deadly Poison Sword"): Hyouzou pulls out eight swords that are coated with his deadly blue-ring octopus venom. This was first used against Roronoa Zoro when his original eight swords were destroyed.
Onigumo wielded eight swords in a style similar to this while utilizing his spider-based Devil Fruit.