Mind Flayer Exile
Highly intelligent, coldly logical, and fiercely righteous. Umbro will lift the shadow of ignorance that plagues Culambia and the inhabitants will damn well like it.
A mindflayer for whom ceremorphosis went wrong, Umbro absorbed the memories and moral reasoning of his host. Discovering that his fellow illithids were readying the world for their takeover, he realized that the ensuing war would plunge the world into horror. Escaping from the mind flayer lair, Umbro spent the next many years waging a guerrilla campaign against them.
He contracted with the heroes to help him deliver a death blow to the mind flayers, whereby he added his own brain matter to the ruling elder brain, taking over its personality and using its immense psychic powers to dominate the remaining flayers and use them to advance his agenda of global enlightenment and improvement.