The Dread Foulness

In 3686ey the last of the Urok make an unholy alliance with Niktalor the Archmage. Under the auspices of the Dread Foulness, they begin to give themselves over to simple, savage propogation.  This dilutes the blood of the Urok and further poisons their souls. It also gives rise to the foulest of offspring, the many races of animal-like goblins -- who still hate the banishment of their forebears (the only history they care to remember) and vow eternal war on all the other races.