Nyx

Nyx is a demon in the series.

History
is the primordial goddess and personification of the night from Greek mythology. Originally said that she was born from chaos and her name means "the mother night." Versions of her birth and origins vary, but one interpretation has her as a creator goddess, laying a silver egg that produces the gods responsible for the creation of the world.

She is depicted as a goddess draped in long flowing black robes that are coated with the void of space and glimmering distant stars. Her appearances in mythology are sparse, but reveal her as a figure of exceptional power. In ancient art Nyx was depicted as a either a winged goddess or charioteer, sometimes crowned with an aureole of dark mists.

One account details Zeus' fear of Nyx is when Hypnos, the god of sleep, reminds Hera of an old favor after she asks him to put Zeus to sleep. Zeus was furious and would have smitten Hypnos into the sea if he had not fled to Nyx, his mother, in fear. In fact, the king of the gods was fearful to the point where he held his fury at bay and in this way Hypnos escaped the wrath of Zeus by appealing to his powerful mother.

She gave birth to many offspring, including Light (Aether), Day (Hemera), Death (Thanatos), Sleep (Hypnos), Doom (Moros), Retribution (Nemesis) the Moirae Sisters alongside many others. In some accounts, the goddess of witchcraft, Hecate was also called the daughter of Night.

Appearances

 * Shin Megami Tensei II: Night Race
 * Shin Megami Tensei: if... / Hazama's Chapter: Night Race
 * Shin Megami Tensei III: Nocturne: Night Race
 * Shin Megami Tensei IMAGINE: Nocturne Race
 * Devil Summoner: Soul Hackers: Night Race
 * Megami Ibunroku Persona: Tyrant Order (PS) / Deity Order (PSP), Final Boss (Snow Queen Quest) as Queen Asura
 * Megami Ibunroku Persona (Manga)
 * Persona 3 / FES / Portable: Death Arcana, Final Boss
 * Persona 3 The Movie: Death Arcana, Antagonist
 * Persona 3 (Manga): Antagonist
 * Persona 3: Dancing in Moonlight: Cameo
 * Shin Megami Tensei Trading Card: Card Summoner: Night Race
 * Digital Devil Saga: Avatar Tuner 2: Nether Class

Shin Megami Tensei: if...
Nyx is a level 51 demon aligned with Neutral-Neutral. Her sprite is a modification of Titania.

Shin Megami Tensei III: Nocturne
Nyx is an enemy in Shin Megami Tensei III: Nocturne. She belongs to the Night Race and can be recruited or summoned once the Demi-fiend has reached Level 70 or above. She has strong affinities towards all magic. Another Nyx can also be seen in Ginza, where she owns a lounge. She appears to be a respected and helpful figure who advises the Demi-fiend to enter the Nihilo base located outside of Ginza via forging an alliance with the Mantra and tells him the way of reaching there.

Shin Megami Tensei IMAGINE
Nyx acts as a boss during the New Moon phase in Shinagawa's ice caves instance. Players can obtain her fusion plugin by giving the red heels drop from the end chest to a Jack Frost NPC in the dungeon's lobby.

Megami Ibunroku Persona
Appearing under the name Night Queen, Nyx appears as the true antagonist for the Snow Queen Quest. Her ultimate goal is to create an "eternal night" and uses the Snow Queen Curse as a means of being brought back into the world. When the Demon Mirror is used to free Ms. Saeko, the Snow Queen comes to her senses, causing the now-free Night Queen Persona to show herself, originally being the Persona of Tomomi Fujimori until the Demon Mirror being used upon her that made her see what she became and separated from her. Appearing briefly with her are two unnamed, but recognizable characters from the SEBEC Quest of the game in masks; the Masked Girl indicates she wishes to destroy the school and created the world they are currently in, and the Masked Man humors the girl, but seems to be following his own objectives. The Night Queen merges with the two becoming Queen Asura for the final battle, but is defeated.

Queen Asura is a member of the Tyrant Order in Megami Ibunroku Persona, but her Order was changed to Deity in both the Japanese and English versions of Shin Megami Tensei: Persona.

Persona 3
In Persona 3 Nyx is the final boss of The Journey, although gameplay-wise the final boss is the Nyx Avatar.

The Persona 3 Club Book explains that Nyx is a celestial-body sized alien called a Planet Eater. Nyx crashed into prehistoric Earth where her body and psyche were separated, with her body becoming the Moon and her psyche staying on Earth. Her "wave-like psyche" existed in contradiction to the psyche of early humans on Earth, so humanity evolved to seal Nyx within the Collective Unconscious as their Shadows. The Fall is when of both Nyx parts which would, if rejoined, rip the Shadows out of the living creatures on Earth while simultaneously destroying Earth. This process is kicked underway by the events of Persona 3.

Nyx lies in hibernation and can only be called by the Appraiser of the Fall, which happens to be the incarnation of the Arcana that was never meant to be: Death. When the Kirijo Group was experimenting on Shadows, Mitsuru's grandfather, along with several scientists, knew about the Fall and willingly embraced it. They eventually succeeded in amassing a large amount of Shadows within the experimental facility and rejuvenated Death. However, Eiichiro Takeba declined and destroyed the facilities, causing Death to be forcibly split into thirteen separate Shadows. Defeating the individual parts would cause them to reunite with the "main" thirteenth Shadow, which was sealed within the protagonist. Death, while within the protagonist's mind, assumed the amnesiac identity of Pharos. Therefore, it is not until the protagonist defeats the remaining twelve Shadows that Death is rejuvenated and reawakened.

Death would then take the form of Ryoji Mochizuki, who was responsible for summoning Nyx and becoming the harbinger of the Fall until Aigis fought him on the Moonlight Bridge, reawakening him to his mission. He would later become the avatar of Nyx. After the protagonist manages to fend off Nyx Avatar, the avatar proceeds to connect to Nyx's true physical body, the Moon. As she descends to Earth, SEES was rendered immobile, leaving only the protagonist immune to her effect. Through the cheering of SEES and his friends' along with the people's will to live, the protagonist ascended to the Moon and battled Nyx failingly, where he used the Universe Arcana's ability (The Great Seal) to repair the weakened seal on Nyx's psyche by turning his own life essence into the seal once again keeping the two parts separate sealing Nyx away by keeping Erebus from alerting her to combine.

It is also mentioned in the guidebook that the Nyx in Persona 3 is named after the Greek goddess of the same name. In Greek mythology Nyx embodied a powerful Mother-Archetype, so the being was named after her due to humanity feeling they were all her children. Conversely, gods and demons emerge from humans as another means to defend their psyche from Nyx. Negative emotions can also help weaken the seal on her psyche, with events like P3's Fall having happened before.

Nyx is not a manifestation of a collective thought (unlike Nyarlathotep, Izanami, Yaldabaoth or Enlil), but an almighty, astronomical entity who appeared from outer space.

The Answer
Nyx was briefly mentioned in the playable epilogue of Persona 3 FES, The Answer. It is later revealed that Nyx herself is neither hostile nor malevolent and that she was alerted to start the Fall from the sorrow, depression, and apathy of humankind represented by Erebus. Upon returning to the time where the protagonist seals Nyx, it is revealed that the protagonist is not planning to seal Nyx away from humanity, but Erebus, to stop a manifestation of humanity's negative will and grief from contacting her to bring the Fall.

Megami Ibunroku Persona

 * Stats and skills change depending on which of the three heads is facing the party.

Black Head (Central)=

Green Head (Right)=

Yellow Head (Left)=

Persona 3
Nyx is fought in a scripted battle following the defeat of Nyx Avatar. Nyx's only attack is "Death", an Almighty attack that deals 9999 damage; the protagonist will automatically endure the hits no matter what. For the first few turns the protagonist will only be able to use Slash attacks, which deal normal damage but do not deplete Nyx's HP. After being given strength from the rest of the party the protagonist will have enough HP to cast the unique skill Great Seal, automatically ending the battle.