Nyx was the primordial/incarnation goddess of night and darkness. There are few mythologies related with Nyx, but one does establish her as one of the most powerful entities that has ever existed.
Hera desired more than anything to usurp the kingdom from her husband, Zeus, because she deemed him unworthy to reign. She recognized that she lacked the strength necessary to defeat him alone and sought assistance from Hypnos. Hypnos used some magic to get Zeus to fall into a deep sleep, allowing Hera to work behind his back. The only issue was that Hypnos was not powerful enough to keep the King of the Gods asleep for an extended period of time. When Zeus awoke, he was incensed by what the two had attempted. He immediately reconciled with Hera and directed his wrath toward Hypnos. Hypnos sought sanctuary in a cave guarded by his mother, Nyx, out of dread. When Zeus pursued him to the cave, he was confronted by Nyx. She pleaded with Zeus to halt his pursuit of her son, and because even the gods fear the Protogenoi, he agreed and ran away.
Nyx cohabited with her daughter Hemera in Tartarus. Nyx would leave Tartarus during the day (as Hemera returned) and fly up from the Underworld, reuniting Erebos. When Nyx returned to Tartarus, Hemera departed and scattered Erebus, revealing Aether and bringing day to the world. Later, Eos, the goddess of dawn, intervened and granted them a reprieve. Following that, Eos and Nyx would depart when Hemera arrived.
Nyx was elevated to a greater prominence in some fragmentary poems attributed to Orpheus. Nyx, rather than Chaos, is the initial principle from which all creation arises in them. Nyx resides in a cave, or adyton, where she bestows oracles. Cronus - who is imprisoned within, sleeping, and intoxicated with honey – dreams and prophecies. Outside the cave, Adrasteia bangs on her tympanon and clashes cymbals, ecstatically shifting the entire universe to the beat of Nyx's singing. Phanes, the bizarre, grotesque, hermaphrodite Orphic demiurge, was either Nyx's child or father. Nyx is also the first principle in Aristophanes' The Birds' opening chorus, which may be inspired by Orphic mythology.
The concept of Nyx's cave or home, located either beyond the ocean (as in Hesiod) or on the rim of the cosmos (as in later Orphism), may be mirrored in Parmenides' philosophical poetry. According to classical historian Walter Burkert, the goddess's mansion to which the philosopher is taken is the palace of Nyx; however, this notion must remain uncertain.
Christopoulos, Menelaos. "Dark-winged Nyx and the Bright-winged Eros in Aristophanes’ “Orphic” Cosmogony." Light and Darkness in Ancient Greek Myth and Religion (2010): 207-20.
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