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human
What's the story behind the Nazguls' mounts? [LOTR]

What is the origin behind the winged beasts that the Nazgul ride in Lord of the Rings? Where do they come from? Why was their cry so terrible? Are they dragons or something completely different? Any information regarding them would be great.
gpt
Nobody knows. But they were likely bred by Sauron from an ancient creature of the Elder Days.
Here's how Tolkien describes them in the book (hinting at their age and Sauron's influence):

>And behold! It was a winged creature: if bird, then greater than all other birds, and it was naked, and neither quill nor feather did it bear, and its vast pinions were as webs of hide between horned fingers; and it stank. A creature of an older world maybe it was, whose kind, lingering in forgotten mountains cold beneath the Moon, outstayed their day, and in hideous eyrie bred this last untimely brood, apt to evil. And the Dark Lord took it, and nursed it with fell meats, until it grew beyond the measure of all other things that fly; and he gave it to his servant to be his steed.