"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).
With regard to the plot "Sleeping Mines of Elathon":
You manage to get the water wheel in the mine working which operates a pump to clear the flooded lower levels. As you explore the dank tunnels of the lower galleries, you can hear the creaking of the wheel above. You enter a low-ceilinged passage and are crawling on your backs, when the creaking stops. The water starts seeping wetly around the back of your head...