Stormrunner said:
I believe that, as so often happens, this harks back to Tolkein. Lord of the Rings didn't have the bazillion other races of D&D, just elves, orcs, and hobbits. There are a few half-elves (Elrond is one, which is why in the movies his daughter has the ability to choose between being an immortal elf or a mortal human - and when he describes to her the sorrow of taking a mortal lover and watching him age and die, he's describing what happened to his mother). Saruman force-breeds half-orcs, the Uruk-Hai. Hobbits apparently don't intermarry much. So half-elves and half-orcs were written into the original D&D.
Yeah, it's kinda wierd how it works in D&D by comparison. The origins of the races in Middle-Earth were pretty different (and there's still no telling how Hobbits evolved from Men, as they seem to have done, somewhere along the line).
I handle cross-breeding differently from one campaign setting to the next, but pretty much.... In Aurelia, few races are capable of interbreeding, because of the differences in their base elemental nature (there are no 'genetics' in Aurelia, but elemental composition is important to determining compatibilities and gross physical properties). Humans are possessed of a unique elemental balance in their nature, so they are uniquely capable of interbreeding with various creatures, though few humans ever do so (the ancient Mentari humans were one exception, some of whom lived among genie-like elemental creatures, who eventually mixed with them in culture and bloodlines). Most other creatures cannot interbreed, though there are some exceptions, like dragons, fey, and many outsiders, due to their highly magical nature.
In Rhunaria, only immortal, corporeal spirit creatures can interbreed with mortal creatures, since they're so innately magical in essence and their physical forms are just a manifestation of their strong spiritual essence; mortals are too different in genetics or elemental nature to crossbreed (the matter of genetics or other concepts is still up in the air with Rhunaria; I haven't decided what exactly governs the nature of different creatures). But half-dragons, half-fey, half-celestials, half-fiends, half-anarchials, and half-axions are possible, as are the resulting partially-spirit-blooded mortal descendants. And the half-races lack their spirit parent's immortality, though their lifespans are unnaturally long (generally twice as long as normal). For reference, true dragons in Rhunaria are immortals, corporeal spirits similar to fey, demons, celestials, and such. They are only fertile for a few months or maybe a year, once every few centuries, and dragons' strange nature and origin results in few offspring (their origin in Rhunaria is kinda wierd).
I do think it would be better to have some sort of process for writing up crossbreeds, similar to statting/pricing a new magic item. The current RAW attempt using templates is unsatisfactory. Frex, if you mate a dragon with a demon, do you get a dragon with the half-fiend template or a demon with the half-dragon template? The two result in very different stats; in an ideal ruleset, they'd end up identical...
Well, if going by genetics or similar concepts anyway..... If the offspring is male, it will probably be primarily of its father's race, or an even mix. If the offspring is female, it could resemble either parent more than the other, but will probably resemble the mother primarily I'm guessing. I dunno. I think the order of types presented in Savage Species would be involved, though. Any offspring of an Outsider would be an Outsider itself; so you'd probably start with a Balor, frex, then add the Half-Dragon template since, according to SS, the Outsider type would override the Dragon type in the 'type pyramid' as being more essential to the creature's being, and you'd end up, for example, a Half-Red-Dragon Balor.
Yeah, that's another thing I dislike, the tendency to create "sub-races" instead of cultures. You don't have Eskimo elves, you have "ice elves". You don't have gnoll monks, you have "flinds". Bleah.
Yeah, it's wierd. Though I like flinds as a smarter, leaderly type of gnoll.

They're getting a major overhaul though in my Aurelia rules, where Flinds are smaller, smarter gnolls with a knack for commanding their larger brethren, and a minor talent for both psionics and magic, allowing them to keep their brutish, selfish, oversized kindred in check.
I don't like the overabundance of subtypes either, though, and I rarely use it. Rhunaria has no subraces, with only two sorta-exceptions: goblins, hobgoblins, and bugbears are all around, essentially divergent breeds of goblin, with hobgoblins being the medium-sized and more disciplined breed, bugbears as the barely-medium-sized-cuz-they're-so-tall-and-burly breed with less smarts, and goblins being the small, nimble, clever-but-cowardly breed; then there are elves, which have only 3 subraces themselves; dark elves and sea elves were created through magical experiments on normal elves though (well, jungle elves are the normal breed in Rhunaria), so there's still only one real breed of elf in Rhunaria, with two subraces that were created through unspeakable acts of magic and alchemy.
Aurelia has only 1 kind of elf, 1 kind of dwarf, 1 kind of gnome, 1 kind of halfling, etc. Few races in Aurelia have subraces, and only with good reason; frex, Spiritfolk (from OA) have numerous subraces because they're the offspring of nature spirits and humans, so naturally they differ based on what kind of nature spirit was involved; and each breed of Spiritfolk is exceptionally rare since nature spirits don't often cavort with mortals, to where the vast majority of people never even meet a Spiritfolk once, of any breed. And Hengeyokai are reincarnated animal spirits able to assume humanoid form, so they differ based on the type of animal they normally appear as.
There are 3 kinds of thri-kreen in Aurelia because 2 were created from normal thri-kreen by extreme environments and either magical or psionic effects. The subraces of thri-kreen are also rather small in population by comparison to normal thri-kreen, since they developed in isolation from thri-kreen slaves or exiles. The six planetouched human races are the Mentari descendants, and vary based on what type of Inner Planes creature they are descended from, but they're fairly limited in numbers on the Material Plane. The four Gith races are all descended from Gith humans that were exiled (forcibly or by choice) to different transitive planes for a long time, exposed to harsh environments and forced to survive through their psionic talents and wizardry alone. And they're extremely few in numbers because of what they had to struggle through just to survive.