Prehistoric fallen angels

I sighed and rubbed at my temples, closing my eyes. "You said the skinwalkers were semidivine?"
"You're using the English word, which doesn't really describe them very precisely. Most skinwalkers are just people-powerful, dangerous, and often psychotic people, but people. They're successors to the traditions and skills taught to avaricious mortals by the originals. The naagloshii."
"Originals like Shagnasty," I said.
"He's the real deal, all right," Bob replied, his quiet voice growing more serious. "According to some of the stories of the Navajo, the naagloshii were originally messengers for the Holy People, when they were first teaching humans the Blessing Way."
"Messengers?" I said. "Like angels?"
"Or like those guys on bikes in New York, maybe?" Bob said. "Not all couriers are created identical, Mr. Lowest-Common-Denominator. Anyway, the original messengers, the naagloshii, were supposed to go with the Holy People when they departed the mortal world. But some of them didn't. They stayed here, and their selfishness corrupted the power the Holy People gave them. Voila, Shagnasty."
I grunted. Bob's information was anecdotal, which meant it could well be distorted by time and by generations of retelling. There probably wasn't any way to know the objective truth of it-but a surprising amount of that kind of lore remained fundamentally sound in oral tradition societies like those of the American Southwest. "When did this happen?"
"Tough to say," Bob said. "The traditional Navajo don't see time the way most mortals do, which makes them arguably smarter than the rest of you monkeys. But it's safe to assume prehistory. Several millennia."
Yikes.
Thousands of years of survival meant thousands of years of accumulated experience. It meant that Shagnasty was smart and adaptable. The old skinwalker wouldn't still be around if it wasn't. I upgraded the creature, in my thoughts, from "very tough" to "damned near impossibly tough."


Turn Coat Chapter 29, Page 268-269