Hybrids

Hibrideach, commonly known in Imperial lands as hybrids, are an extreme rarity. All the five races of Aarden are capable of cross-breeding, however, such taboo is placed on the practice by all cultures that it is extremely rare. At one time, human-elf and orc-goblin hybrids were not unheard of however it was banned by the Illyrian Empire out of fear of the exceptionally powerful offspring produced from such unions, while the status in the orc realms is unknown, thought the mating is thought rare due to the status of goblins in their culture.

-Imperic Encyclopedia, Volume I: The Races of Aarden