So I've had this idea recently after reading too much apocalyptic fiction and playing too much fallout.
My idea goes like this:
About 350 years ago, a secret society formed dedicated to protecting mortals from paranormal events. Dragons, ghosts, zombies, vampires, unicorns, bigfoot, and payphones are all very real, but very well hidden. They've had a major impact on the outcome of global events, guiding the world where they thought it needed to be. Always hidden, never seen.
And then in the year 2050, a great disaster occurred. A third of the world's population suddenly perished. Nobody was ever sure what caused it. In the days that followed, about half of the world's population was dead or had disappeared. Entire governments had fallen, the world was in ruin.
It's now 2090, and The Agency now works out in the open, and there's no longer very much room for secrecy in this semi post apocalyptic environment as they try to hold things together.
Meanwhile, a new group called Unity Force, set out by their two charismatic leaders, sets out to help rebuild the world in it's own image.
So this setting will something of a post apocalyptic shadowrun, it will have elves, orcs, golems, dragons, amazons, spellcasting, and the like, but it will also have some fallout-esque features like guns and robots. How does that sound?