The titular character of the comic, movie, & two-part OVA of the same name. Especially depicted by his right hand's birthmark of the hexagram (Star of David). He is intended to be the Child of Destruction, to bring about the end of world fortold by the Holy Bible. Yes, I am serious!
He was trained severely by a Kung Fu master, whom he succeeds, learns to utilize his chi (basically making him into a human slaughterhouse). Has a twin brother with a swastika on his hand, who uses telekinetic powers, and a fanatic father who claims to be God.
When heated up, his fist (possibly his body too) may exude an aura, and his eyes may even release a thin steam.
Among his feats are knocking elephants down, defeating a man aided by internal wires, moving a nuclear reactor's control rods, dispatching an undead with his body heat.
It may be obvious, but he is inspired by Kenshiro, hero of the Fist of the North Star/Hokuto no Ken series. But he also uses chi like peeps in Dragon Ball (but uses the Kamehameha-like Kantsuu Reppa very VERY sparingly).
Riki-Oh is a pretty cool guy. Eh sends your karma to Hell and doesn't afraid of anything.
"...Pass on to the next life!"
"This brother will turn your bad karma into ash!"