Moxus was stolen from his Pride in the Tropics at a young age by slavers. Raised on ships by other slaves, he quickly became a great lookout, and eventually merged into the crew of a slaver vessel. As he aged and grew in strength and beauty, it was decided that he would be sold for a hefty profit.
He was sold to a mage who was interested in seeing what magical potential High Felines possessed. In a decade, Moxus could produce Arcane Magic in quick blasts - perfect for combat, but nothing really else. Abandoning the project, the mage sold him on to a wealthy noblewoman.
The noblewoman wanted a loyal protector and had Moxus trained to handle a fancy weapon - a double-ended great waraxe. Combined with his control over combat magic, he made the perfect bodyguard. Moxus milked this relationship for all he could, insisting he needed to learn more combat skills to protect her better. Finally, he had amassed such a knowledge of battle that the noblewoman decided it a good idea to put him to work in the illegal fighting pits of Halfmoon and gamble on his success.
One especially bad fight left him in such a condition and lost her so much money that she abandoned him. He was found by a group of sympathetic students passing through Halfmoon, lost while sightseeing. They took him to an inn near the docks where they were staying and nursed him back to health. Because of his last defeat in the fighting pit, he has a massive scar reaching across his furry chest, barely having missed his heart.
With his strength nearly back to full, Moxus spent a few weeks on the docks just fishing and selling his catches to the inn so that he might continue to stay with his newfound friends. The docks was where he met a woman named Rasheba Heartstone, hiring crew for her vessel to return home after some of her men retired. Moxus bade farewell to his friends and went with her.
Moxus proved his worth only a few days into the voyage to Caybourne. Flanked by two pirate ships, Rasheba ordered the crew to outrun them, but they were a larger, ungainly vessel and were soon set upon. Moxus had no weapon but went in with claws and teeth, jumping the railing and setting upon the first pirate ship with a ferocity Rasheba had never seen before. He caused such a distraction that Rasheba and her crew were able to dispatch the other pirate crew before coming to Moxus' side. Both pirate crews were massacred and Rasheba ordered her crew into skeleton-sized crews so they could take the pirate ships home and repurpose them.
Moxus quickly found a place in the Ludlow Accord after that incident. He rose through the ranks and was in the perfect position to take the role of Commodore when his superior stepped down.