Making the threats numerous, ambiguous and not readily explained offers much more ground to build upon. If not everything is known or understood, it makes any danger just all that more mythical. You have to ask yourself then, even as a reader who has the "eye of God" view of the story, "What [i]is[/i] actually happening here?"

I have no doubt there are prophecies and legends, fantasy would not be the same without them as we are all well aware, but putting a spin upon them as potentially filled with error or "not quite true" makes them more novel, more fascinating. For example, the submission I put forward has no real answer; everyone who did know is dead and those who truly knew are long since dead. Some people believe they know, but are too afraid of the answers because it challenges their beliefs - they would rather live in the perceived safety of their beliefs despite contrarian evidence.

Spelling nothing out for certain short of the obvious, such as places, peoples and personalities does well to these ends.