Few know of this place, and far fewer know of its location. This is a good thing, for nothing wholesome comes from here.
How long they carried him through those back tunnels, illuminated only by the flickering of torchlight, he had no idea. Then light seemed to explode when they reached the massive chamber. All around, unbelievably large red crystals captured the light of the flames and seemed to multiply it.
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.