BiggusGeekus said:
What really gnaws at me is the vast array of half-species that are the product of a sexual assult. In the case of the half-orc it's even written into the PHB. Maybe I overdosed on my political correctness pills, but I really don't think that's a necessary solution to explaining the origins of the half-races.
Whatever happened to insane wizards? Those guys never go out of style.
In my current campaign, half-orcs form self-sustaining populations in border regions near orc/human borders. The original population starts from the usual mostly-rapine explanation but over time, the outcast half-orcs have tended to gather together. Frankly, half-orcs are most attractive to other half-orcs. Humans look to frail and breakable and orcs look too brutish, although both humans and orcs will occasionally breed into half-orc populations (helping ensure a healthy diversity in these relatively small populations). Half-orcs vary enough in appearance that some are attractive enough to either orcs or humans to find mates in those populations. The 1/4 and 3/4 orcs usually end up breeding back into the half-orc population and just represent a more extreme variation in the half-orc range.
Being both stronger than humans and smarter than orcs*, they tend to resemble barbaric human cultures. Their technology is superior to that of orcs and they tend to be civilized enough to trade with humans and yet aggressive enough to earn the grudging respect of orcs (making them a key trade partner for orc tribes smart enough not to raid them). Alignment-wise, the populations tend to be Chaotic Neutral with a strong emphasis on personal strength and personal honour. Nomadic horse tribes are common among half-orcs in plains and steppes regions - unlike orcs, half-orcs quickly clue in to the uses of horses as steeds and work animals rather than food.
* In our campaign, both half-elves and half-orcs benefit from the human skill point bonus. This has not proved unbalancing for either race. Humans are still by far the most popular race among my players, both for RPing reasons and mechanics reasons (since only they get the extra feat). However, the extra skill points make half-elves more adaptable than elves and half-orcs significantly better at skill checks than orcs.
As for half-elves, well, IMC almost all elves have human blood to some degree. The tiny number of full-blooded elves are an immortal 8HD fey race that I've restricted as NPC only. PHB elves have human blood, are mortal (but long-lived) and strongly resemble their true elven ancestors. PHB half-elves have even thinner elven blood, fewer similarities to true elves but are culturally elves. The elven nations mix with human populations because the elven race is very slow to reproduce and their very long-sighted worldview gives them little dynamism. The human-elven hybrids rapidly outbred the real elves and now form 99%+ of the "elven" population. The true elves form an aristocratic caste in their society, guiding their hybrid brethren with their wisdom while benefitting from the productive, curious and driven nature of their hybrid lower classes. Even the PHB half-elves are long-sighted and graceful by human standards, but compared to the real elves, they are industrious innovative dynamos. Busy worker bees compared to the sedentary queen bee fey aristocrats.
Other half-breeds exist but they are more uncommon. Orcs and the more brutish giants seem to be less picky about the species of their partners. Dragons and outsiders are prone to straying across the species barrier too, although for them it is as often to produce loyal minions than to "scratch an itch".
Insane wizards account for most of the wierdest half-breeds, particularly the ones where the sheer physics involved in the mating boogle the mind.
