I thought of this other day. Humans are the most boring race in fantasy RPG’s. Yes, there’s that human diversity, spirit and all that but compared to everyone else they’re kind of blah. So why not twist things up a bit? Let’s make them and their place in the world just a little more interesting.
Bottom of the Food Chain: Dwarves are resistant to poison. Many races can see in the dark. Simple things like this don’t exactly make humans the best. So play it up. They’re at the bottom of the food chain. They’re the lowest on the totem pole. You get the drift. They might not even have their own cities and kingdoms. They just hang out with the other races.
Invasive Species: Who says humans have to be natives to the setting? Maybe they’re from another world or plane. They showed up, escaped, got exiled or whatever. Anyway, they’re the newest race and they’re breeding like cockroaches or kudzu.
Not A Pure Strain: Maybe humans are the result of an odd pairing. Maybe they’re half-dwarf/half-elf. Neither of the ancient ancestors want to talk about and they probably blame each other for the mistake.
Wizard Did It: Yes, it’s the go-to, pat answer but it can work. Humans are artificial race created by some ancient and probably alien wizard. Maybe laughs, labor, or experimentation.
I’m sure there are plenty more ideas out there. Just run with it, folks. Everything in your setting should be interesting.