Wrath-Amon was a wizard of great power and evil, who was once a mere gila monster. The wizard of Stygia, Ram-Amon, also a servant of the evil god, Set, created him to be a perfect servant, giving him the strength of a hundred men, ruthless intelligence and cunning. But the servant was too cunning and stole the Black Ring, and used it to imprison Ram-Amon. Set agreed to make the creature into his new servant and reformed him into a powerful Serpent Man named Wrath-Amon.
Wrath-Amon ruled the Serpent Men on Earth for many decades and his cruelty and evil became legend. Soon, he was charged by Set to collect enough Star Metal to melt into discs to place atop seven pyramids so that Set would be freed from the Abyss and return to conquer Earth. While doing this, Wrath-Amon made a grave enemy of the Cimmerian barbarian named Conan when he used the Spell of Living Stone against his family. Conan vowed to restore his parents and destroy Wrath-Amon.
Wrath-Amon enacted many schemes to destroy Conan and his friends, and complete his task to free Set. While he failed to destroy Conan, after a couple years he succeeded in completing the pyramids and bringing Set to Earth. Set rewarded Wrath-Amon by making him immortal, and as long as Wrath-Amon held the Black Ring he'd be invincible. In their campaign to stop Set from destroying the world, Conan and his friends attacked Wrath-Amon in his pyramid, and after a fierce battle and one final duel, they succeeded in getting the Black Ring away from Wrath-Amon. Conan next used the Amulet of Vathelos to return Wrath-Amon to his reptile form.