Nyx

"Of course not. I would not let my horses eat you, any more than I would let Akhlys kill you. Such fine prizes, I will kill myself!"

- Nyx threatening Percy and Annabeth

Nyx is the Greek goddess of the night. She is a shadowy figure in Greek mythology but from the extracts about her, it is gleaned that she was a figure of great beauty and power. She was the female personification of the night, and a daughter of Chaos. In her chariot, pulled by two dark horses, she carries the mantle of night, covering the world with her brother/consort's darkness. It is also said by some that she is the goddess of hellhounds. She lives in Tartarus in the Mansion of Night. She stays there only during the day and leaves Tartarus during the night. Her Roman form is Nox.

History
Nyx was born directly from Chaos, the protogenos of the lower air and eldest of the immortals. She married her brother, Erebus, the Primordial god of depth and darkness, and together they had many children. Once, her son Hypnos angered Zeus by putting him to sleep under Hera's orders so she could shower his son Hercules with misfortune while Zeus was asleep. Zeus found out about his involvement and chased Hypnos who quickly fled to his mother, Nyx, whom Zeus obviously respected enough that he held his anger at bay, not wishing to offend the great goddess. Another myth is that Nyx's daughter, Hemera (Day) left Tartarus when Nyx entered it, creating night and day. According to some Greek articles, Chaos did not exist and Nyx was the first divine Entity, promoting her power and importance even more. Her son Moros (Doom) is mysterious as well and is believed to be omniscient, omnipresent, and omnipotent, as he drives all things to their ends. One example is that the Fates, her daughters serve her.

Nyx's Children
Nyx had many children:

From Erebos:
 * Hemera (Day)
 * Night: essentially a male copy of herself and twin brother to her daughter Hemera.
 * Ether (Light)
 * Epiphron (Prudence)
 * Thanatos (Non-violent death)
 * Hypnos (Sleep)
 * Sophrosyne (Self-control, restraint, discretion)
 * Dolos (Trickery and deception)
 * Eleos (Mercy, pity and compassion)
 * Fates - (Personifications of Destiny)

From Partenogenesis (by herself):
 * Momo (Satire)
 * Apate (Deceit)
 * Ponos (Hard labor)
 * Moros (Doom)
 * Keres (Violent death)
 * Charon (Ferryman of Hades)
 * Philotes (Affection, friendship and sexual intercourse)
 * Geras (Old age)
 * Nemesis (Retribution, Balance)
 * Eris (Discord, Strife)
 * The Furies (Vengeance)
 * Oizys (Distress)
 * Styx (Boundary between life and death. In other myths, daughter of Oceanus and Tethys)
 * Elpis (Hope)

By the blood of Ouranos:
 * Lyssa (Madness)

The House of Hades
Even before meeting with Nyx, nearly every creature in Tartarus shows a fear of her (even some Giants and Titans) to the point of only referring to her as Night. However visiting Akhlys for the Death Mist requires Percy and Annabeth to pass close by Nyx's domain if they hope to escape from Tartarus. Unfortunately after Percy and Annabeth manage to gain the Death Mist and defeat Akhlys when she double-crosses them, they wander too close to Nyx's territory and she reveals herself to them.

At first, Annabeth and Percy are too stunned to speak, both because of Nyx's intimidating entrance and because she is able to see them, even with the Death Mist. Percy also worries that the horses that pull her chariot will eat them. Nyx admits to them that she wouldn't allow her horses to do such a thing, as "Such fine prizes, I will kill myself!"

Annabeth uses Nyx's wording against her and tells Nyx not to kill herself. This causes Nyx enough confusion that Annabeth quickly takes charge of the situation and convinces Nyx that they are on a tour of Tartarus, but Nyx isn't part of it. This greatly offends Nyx as she gets more and more wrapped up in Annabeth's lie. When Annabeth claims it may be because Nyx isn't important enough and how they could meet some of Nyx's children instead, Nyx becomes furious and summons all her children, including Geras, Eris, and more minor gods and monsters, which are all the worst terrors in existence. As Percy and Annabeth prepare to try and take a picture, they mention the Doors of Death and Nyx tells them that the only way to reach it is by entering her home, the Mansion of Night. After hearing this, they agree to take a picture with her favorite child. After hearing this, her children begin to fight amongst themselves over who is the worst terror. When Nyx is blinded by darkness, Percy and Annabeth slip past her and run into her mansion, escaping on the other side and over the River Acheron, out of her grasp.

Appearance
Nyx was described as a churning figure of ash and smoke, as big as the Athena Parthenos statue (which was 40 feet tall), but very much alive. Her dress was void black, mixed with the colors of a space nebula, as if galaxies were being born in her bodice. Her face was hard to see except for the pinpoints of her eyes, which shone like quasars. When her wings beat, waves of darkness rolled over the cliffs. She rode in on a chariot that was made out of Stygian Iron pulled by two massive horses that were black except for their silver fangs. Their legs floated in the abyss turning from solid to smoke as they moved.

Abilities

 * She is an extremely powerful goddess, being one of the Protogenoi. She is so powerful and terrifying, that many Giants and Titans fear her.
 * Umbrakinesis: As the protogenos of night, she has divine authority and absolute control over shadows and darkness.
 * She can surround enemies with shadows.
 * She can use darkness to create portals to travel from one place to the next (Shadow Travel).
 * She can use shadows to cover oneself in darkness to become invisible.
 * She can see through darkness while her enemies cannot.
 * She can heal herself and others (minor injuries).
 * Shadow Mimicry: She can morph into (living) darkness/shadow.
 * Night Empowerment: She is stronger at night or in dark places (e.g. Tartarus).
 * Circadian Manipulation: She is capable of controlling the movement and rotation of planets thus enabling her to change the flow of night and day.
 * She can control nocturnal animals such as owls & bats.
 * She also carries the Mantle of Night.

Trivia

 * Her horses were called Shade and Shadow.
 * Somehow, Chaos and Tartarus were able to father Nyx, despite both being considered male. However, it should be noted that in mythology, Chaos is mostly described as genderless.
 * The symbol of Nyx is a star in a crescent moon which is quite similar to the symbol of modern Islam and the flag of modern Pakistan and Turkey.
 * In the Illiad, there is a reference to Nyx having power over men and gods alike, and Hypnos seeking refuge with her for he had angered Zeus, even though still angry Zeus let him be for fear of angering Nyx instead.
 * Her Roman form, Nox, is also the name of a spell in the Harry Potter series that creates darkness. This probably more due to the fact that nox is the Latin for "night," rather than named after the goddess.
 * In June of 2006, the "International Astronomical Union" dubbed one of ex-planet Pluto's moons Nix in honor of Nyx. They spelled it with an "i" because there was already an asteroid with her namesake.

Gallery
Nyx