About Elrath, about Ashah, about all the Elemental Dragons. Why do mages need so many beastmen? Like, they did it just for fun, thinking, "Oh, what will happen if we connect the top half of a slave with the bottom half of a pig?"
Still, centuries of practice have yielded results; in the seventh game, there is a kobold hero who, as far as I understand, has retained all his dwarven skills and memories, while the first cyclops shot lasers from their eyes at mages and ate goblins, and goblins bred right in the laboratory.
And you probably have to try really hard to get a centaur, and not a minotaur with a horse's head) and a four-armed rakshasa is something else entirely.