Btw, looked around several sources for Nyx (not in dictionary, but Nixon's middle name was Milhaus :P)
Anyways, this is what I found from the nyx homepage:
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Nyx, the Spirit of the Night, was spawned from the primordial Chaos. After mating with Erebus, Nyx birthed the Upper Air (Aether) and Day (Hemera). On her own she gave birth to Doom (Moros), Death (Thanatos), Sleep (Hypnos), the Fates, and Nemesis. Her power is said to be great, overwhelming even Zeus. She lives in the palace of Tartarus and goes forth onto the world each night, traversing the heavens until daybreak.
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Hmm...so apparantly she's the one who made all the lesser gods in Greek Mythology.
Btw, do the Trow ever mention the sex of nyx? perhaps it really is a female in the Myth world...