God of fighting clerics and besieged cities, Petra is reputed to have been a great warrior in his time. He traveled the world saving many human lives from a powerful, but unknown enemy. Lending a hand anywhere possible, Petra became known for turning the tide of many hopeless battles. He took special interest in sieges and knew the strategies of war, the operation of war machines, and was adept at training young fighters. War was not constant, though. During times of peace, Petra continued to travel and explore the civilized nations. He was proficient in finding weakness in the human heart, often stirring up the arrogance in rulers and the pride of the poor.

Before long, riots and wars would begin with Petra aiding the most worthy. During one such war among the Traladarans, he disappeared for three months. At the most crucial point when a leader's stronghold was about to fall, Petra arrived wielding great magic and powerful weapons against the attackers. Many defenders rallied behind him as he decimated hordes of attackers. The tide quickly changed and the remaining attackers fled the battlefield. Prior to celebration, he left quietly, but hundreds of men followed him into the wilderness. Months later, he told his followers, 'Leave so that I may finish what is begun. Retain my ways and remain worthy.” Not a single man pursued him as he walked into the depths of a remote cavern to never return.

Petra's followers returned to civilization with a belief that he stayed with them in a spiritual sense. Before long, some of these men began to manifest martial magical powers. Word spread like wildfire and small mercenary bands, claiming to follow Petra, began to form. Continuing to voice a belief in Petra, these warlike bands were demanded across Karameikos. Eventually, Petra worship became a common religion, with its worshipers in high demand.