Mostrassu was born over a thousand years ago, in the land which now makes up Belestar. Mostrassu, like most lizard centaurs, has been a loner for most of his life, preferring to spend the days alone. Unlike most Lizard centaurs, he was fond of travelling, and used to wander far and wide over the lands of Edhelnore, and even a few excursions into what was to become Rhutalath. On these journeys, he occasionally spent time with the Elves, who taught him songs and spellcraft, and he came to enjoy their company. Over the centuries Mostrassu watched in anger and fear as the Vultani arrived, followed by the Imperials, and the Elves began to leave in droves. He grew bitter as the men began to manipulate and destroy the land.
Mostrassu moved eastwards, in an attempt to escape the mannish settlers. Here he encountered the Pachacaca. The Pachacaca worshipped him as a nature spirit (they believe that all lizard-centaurs are enlightened versions of themselves), and fed him, and sang to him. Mostrassu quickly realized that these fast-breeding lizardmen were the perfect cure for the destructive mannish races. He could use them as an army to wipe out the Vultani and Imperials. Yet the Pachacaca, despite their adoration, feared the Humans, and believed they were the highest gods, and refused to listen to him. Mostrassu, angered with their complacency, left.
A few laters, he stumbled across a baby in the woods. Despite its Vultani appearance, he took pity on it, and took it home to his cave. Besides, the child was half-Elven, everything that Mostrassu admired. Mostrassu reared the child, and raised her and began to teach her philosophy and lore. He named her Engessia, a lizard-centaur name meaning Fated, (which was changed to Hengestia, a Vultani name). Mostrassu began to love Hengestia as his own, and was devesatated when she left to meet her own people. When she returned, sullen and rejected, Mostrassu began to remember his deep hate for the Vultani.
Mostrassu once again vowed to rid the land of the Vultani; and Hengestia was the ultimate solution. Her similar hatred could be harnessed, and the lizard-mens reverence of the Vultani could be manipulated. So, on the holiday of Ki-Pachu, Mostrassu led Hengestia to the Pachacaca capital. She was instantly worshipped as a deity by the superstitious lizardmen, and crowned queen. Hengestia had more influence with the Pachacaca, and began to send them to war against the hated Vultani.
Now, Mostrassu lived in Ixia with Pachunama, serving as her vizier and consul, and as her mouth to the lizardmen. Extremely patient, and slow to anger, he is slowly biding his time till the time when the Vultani can be removed, and the Elves can return. Although he loved Pachunama as a daughter, he is not afraid to manipulate her feelings and her anger to achieve what he wants. Mostrassu is the official high-priest of the Pachucaca, despite the fact that he does not believe in or worship the lizardmens gods.