Katō Jutsu
Katō Jutsu (火問術, Fire Combat Technique): Fire-breathing style used by Mr. Heart in Hokuto Muso video-game, Gallon in Hokuto no Ken and a Fat Thug in Soten no Ken.
Gallon's style

Ryūto Kaen Jutsu

Ryūto Kaen Jutsu (竜吐火焔術, Dragon Belch Flame Technique): Fire-breathing technique used by Gallon, the Captain of the Ken-Ōh Invasion Squad at Mamiya's Village.

Mr. Heart’s style

Cho Katonjutsu

Chō Katon Jutsu (超火遁術, Super Fire Release Technique): Bringing out his custom metal drum filled with oil, Heart gulps down its contents. He then blows fire to burn the foes in front of him. He finishes the move by throwing the drum into the flames, letting it explode.