Prima Beastia was originally a mage specializing in magic that could tame animals for a variety of purposes: pets, beasts of burden, research and whatever else! Prima Beastia was especially talented in taming animals and granting them abilities that would make them ideal partners in battle. Warriors and adventurers from the world over sought him out to acquire a familiar of their own. Over time, the more beast magic he used, the more he could empathize with the animals he tamed. Before long, his thoughts and behavior become more animalistic in nature and he soon abandoned any semblance of having a human lifestyle.
He began to desire having a form more in tune with his animal-like mind, and researched ways he could morph himself into an animal of his choosing. When he perfected the spell, news spread that Prima Beastia could now grant people the ability to become animals. People flooded his hometown looking for a chance to pay him for that ability. But with his new mindset, money and material things had absolutely no value to him. He abandoned his life, and became a wanderer, morphing into new animal shapes every day to explore the world of beasts. During his travels, he noticed that the animals he tamed were not entirely happy, and many of his familiars poorly treated. Feeling anguished that he was the root of this suffering, he swore to forsake all human life and protect animals instead.
Today, Prima Beastia wanders the world with his cohort of animals, attacking towns and cities to free as many animals as he can. More than just a nuisance, Prima Beastia is a force to be reckoned with and can cause enough damage to devastate whole cities if allowed to rampage unobstructed. The Guild of Magic has him labeled as Subdue At All Costs whenever he is spotted. Prima Beastia can never be subdued for long, but that has only made him a rite of passage for many students of beast magic who seek him out to test their skills!
(yikes that was long, lol)