Our story begins at a point in the Universe not unlike where you are now sitting, drinking your government-sanctioned stimulant, dreaming of the day when you, too, will own your own personalized luxury home on 0.3 acres of land, with a stunning view of, well, the neighbor's personalized luxury home on 0.3 acres of land. Except this point in the Universe is much more exciting, fine-smelling, and generally a better place to be than yours.
So, anyway, at this particular point in the Universe, on a day not entirely unlike today, two entirely unrelated mythological pantheons collided, resulting in a fast friendship between a Little Boy Bound to be Eaten by the Architypal Crone and a Faceless Beast That Waits for the Hero to Dispatch It. Which, as you might have guessed, was not the intention of the various storytellers involved, but that's what happens when people stop reading all the really cool stories and start checking the Financial Section every 12 minutes. There's only so much space to go around in the collective consciousness, you know...