Half-breeds. Another issue that makes little sense. Genetically speaking, half-breeds shouldn't be possible. Especially between, say, an orc and a dwarf. It shouldn't produce anything, it's clear the two races have drifted too far apart to ever properly have children. Yet, I wanted to keep half-breeds. So how do I fix that issue?
Well, ten thousand years ago in the world's history, there was an apocalypse event. Prior to that, there was an ancient empire known as the Imperium. What few records survived the apocalypse event, tell of basically only humans. There's no mention of elves, dwarves, or other stock fantasy races. The only reference to other species is of superpowered, supernatural creatures, capable of wiping out thousands of men single handed. Think like Dragons, or giant spiders with magical powers, et cetera. Mortals back then didn't have much of a capacity for magic. There was a Mage's Guild devoted to trying to resolve that. They did.
It resulted in the apocalypse. A detonation of magical energy with the equivalent power of a tsar bomb, which spread in every direction like a cancerous tumour. It wiped out the Imperium and killed most of the continent's population of humans, but it also severely weakened the supernatural entities, and all of a sudden, mortals could use magic.
At the same time, some few hundred years later, records suddenly appeared of other races.
Because of the dark ages imposed by the apocalyptic event, nobody gave it a second thought. Nobody that survived remembered what the Imperium was anymore, so they didn't remember the whole "humans only" bit.
Yet, some few within the universe who are ancient do actually realize that the similarities between the mortal races can't be passed off as natural. It also can't be passed off that only humans are capable of breeding with every other sapient mortal race with no problems and no need for magical assistance.
Now, suddenly, it makes a little more sense. Plus it adds a mystery. Maybe there were other races during the time of the Imperium, and the records speaking of them didn't survive. Maybe the magical event left a few more survivors than everyone originally thought there were, but not without a few mutations. No matter what the truth is, it's unsettling enough to be interesting.
