The Greek goddess Nyx was the goddess of the night and, by some accounts, the daughter of Chaos. She lived in Tartarus with her children Hypnos, the god of sleep, and Thanatos, the god of death. Some accounts say she was also the mother of Eros.
Nyx makes an appearance in Homer's Iliad, some poems attributed to Orpheus and the play "The Birds" by Aristophanes. While she was never a focus of any cults, she had an oracle at Megara and a statue devoted to her in the Temple of Diana at Ephesus. While she does not appear in many Greek myths or stories, she was believed to be so powerful that Zeus himself feared her.