Aeon was a Spartan soldier who, like Sophitia
, received a vision from the god Hephaestus telling him to destroy Soul Edge
. Armed with a sword and shield given to him by Hephaestus, he set off on his journey. But, he soon found himself lost in a vast desert collapsed from dehydration. Luckily, he was found by a group of travelers that brought him to their village. He wasn't given the chance to repay them, as the Evil Seed soon descended upon the village. It caused Aeon to go temporarily insane and slaughter everyone in the village.
Kunpaetku, leader of the Fygul Cestemus cult, heard of this and had him captured, to be used as a subject for experiments. These experiments changed him into the first of many lizardmen. He was then sent to kidnap Rock's
son, Bangoo, so that he would be lured to Europe. Lizardman was eventually tracked down and defeated by Rock for his deeds, while aiding Astaroth
, the cult's other servant, in his pursuit of Soul Edge.
When Soul Edge is defeated, the power of Soul Calibur frees Lizardman from his brainwashed state, but left his body in it's current state. He set out to find a means of returning to his original form, but upon realizing he had no place to go, he questioned why Hephaestus hadn't helped him in his time of need. He threw the weapons he had been given to the ground and found a new resolve. With a new axe and shield at his side, he sought out Soul Edge so that he could destroy his god with the very weapon he feared most.
His human memories and emotions slowly started to fade, until he had almost become a beast. Soon, other lizardmen had found him, and using his superior strength and combat training he easily dominated them. He became their leader, and lead them on wild rampages.
But, his dreams still held his memories of being human. Not knowing what he truly was anymore, he felt a deep emptiness and realized that he no longer had a soul. Wondering what had happened to it, a memory returned to him. His soul was inside Soul Edge. Realizing this, he continued his search for the sword, to become whole again and reap his revenge.