"Uncle Humblestaff?" the young hero responded. "Of course I know the man. Wouldn't have had a chance at the academy without a word from him. He's the big guy over there, surrounded by all those adventurers."
The only remnant of the Shattering, Lydecker Cain found himself the solitary survivor of a universe that was no more than shards of glass.
"Have you ever felt like there’s a world just beyond ours? Some sort of strange dimension, a light dancing just beyond our fingertips? Well, I’ve touched that ‘sacred’ world, and I know its true face."
History is full of interesting and exotic people who can help to populate your world. They can help illuminate the range of what people think is possible for your world (or you can consider them PCs run by players not in your game).
The PCs are accosted in a major city containing at least one famous fortuneteller / prophet of the future. They are informed that their as-yet-unborn child will (insert terrible evil), and that, although they are very sorry, the PC must be executed to keep this from happening.