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The Nine (often represented as the IX), also known as the ennead, are a group of enigmatic entities affiliated with the planets of the Sol System. They control Unknown Space, a mysterious realm whose nature is poorly understood.
The Nine are sentient beings composed of dark matter, which developed cognition after being pulled into loops by the gravity of Sol and its planets. Their existence is predicated on the existence of those planets, particularly the life that developed on them, as the motions of lifeforms cause gravitational perturbations that drive the Nine's ability to think. The Nine's primary concern is sustaining their own existence, whether by protecting the life on which they depend or by finding a way to end their reliance on it.
Despite their virtual omnipresence within the Sol System and the universe with their influence of Dark Matter, the scope of their power over the world of "normal" matter is limited, and so they primarily act through a handful of agents, emissaries, and associates. They appear to be capable of freely manipulating the dark matter that composes themselves. They are also able to manipulate and even synthesize regular matter under certain circumstances, such as through the portals of Cocytus.
At present, the Nine are divided into two factions. One faction, consisting of five members, seeks to study the Light and use it for their own purposes, and is responsible for sending Xûr, Agent of the Nine and The Emissary to interact with the Guardians. The other four seek to free themselves from their dependence on matter-based life and the Light, and to that end have experimented with creating their own realms through spacetime engineering and the creation of dark matter-based black holes, which would serve as gravitational foci independent from those provided by the realm of normal matter.
The Nine appear to have some ability to predict or see the future; the Prophecy Dungeon includes symbolic representations of future events such as the rise of Eramis, Kell of Darkness, the disappearance of Io, Mars, Mercury and Titan following the arrival of the Black Fleet, and the arrival of Empress Caiatl in the Sol System.
As revealed by the Nine to Lavinia Garcia Umr Tawil, the Nine originated from streams of dark matter particles passing through the galaxy and the solar system. As dark matter only interacts with normal matter through gravity, these streams were drawn to the cores of the Sun and its orbiting planets. The infalling dark matter was then flung back into space, before being pulled in again to form endless loops. These loops formed the basis of emergent consciousnesses that would become the Nine.
The Nine did not truly "awaken" until life evolved within the solar system. The movements of life-forms resulted in perturbations to the loops of dark matter particles cycling through each celestial body, creating waves that formed the basis of complex thoughts. According to Lavinia, the dark matter of the Nine passes through every living thing and every iota of matter in the solar system.
The Nine were cognizant of their dependence on all life and the worlds of the Sol System: if that life ended, so too would the Nine as thinking entities. They began searching for a way to end that dependence and sustain their existence independent of it. Two factions emerged after the arrival of the Traveler to Sol: one faction sought to harness the paracausal properties of Light to construct living bodies for themselves out of regular matter, the other seeking to create a pocket universe with physical laws that could accommodate them.
For most of the City Age, little of the Nine was known outside of the cryptic sayings of Xûr, Agent of the Nine. Osiris is said to have met with the Nine on Europa, and before his exile had an obsessive interest in them to the exclusion of his duties as the Warlock Vanguard. Nonetheless the Nine had a vested interest in helping the City, tasking Xûr to sell powerful weapons to Guardians. Following the Red War, the Nine have taken an active interest in Guardians, and hosted the Trials of the Nine through their proxy, The Emissary. Emperor Calus is dismissive of their efforts.
The Nine have an alliance of sorts with The Reef, but their loyalty is in doubt following the release of Skolas, Kell of Kells at their command. The Cabal know of them as the Ennead.[note 1]
During the Reef Wars, the Queen's Wrath Sjur Eido was killed by an unknown party, and her bow stolen. A strange coin was left on her body as "weregild", suggesting that the Nine were in some way involved with her death.
Arrival of the Taken King
Shortly after the battle of Saturn, when Oryx invaded the Dreaming City, the Nine debated about what to do regarding Oryx's incursion, for he threatened all life. Some members seemed to blame Mara Sov for worsening the situation, claiming that her actions had "ruined everything." Oryx soon took Riven, after which the Nine were driven into a frenzy. During this time they would debate whether or not to destroy the Ahamkara, and if they did "Done cannot be undone! Everything is lost!" Although their wording is ambiguous, the Reextinction lore entry suggests communications between the Nine during this time indicate that they knew of surviving Ahamkara other than Riven and that they killed them in order to prevent them from falling into Oryx's grasp.
The Red War
Sometime during or before the Red War an Awoken named Orin (and potentially an agent of Mara Sov) sought out nine Ghosts who had gone beyond the Solar System and inquired after their findings. Receiving only a set of coordinates she left them. She also found several "deep-orbit minds" in the midst of her search. Orin soon encountered some of the Nine herself. After warning her of the possibility of going mad from the conversation and of a potential price as consequence, they tasked her with finding three "worthy keys". They then commended her for seeking them out, for her resourcefulness in acquiring a ship and her decision to avoid "a golden snake who poses as a god".
One of the Nine was responsible for blinding the Guardians to the arrival of the Red Legion, allowing Ghaul to successfully attack and occupy the City. This member of the Nine did so with the goal of learning how to take the Light, but that particular member of the Nine was severely punished, as Ghaul's success led to the deployment of the Almighty, which would have destroyed the Sol system along with the Nine had it not been disabled.
Whether before or after Orin/the Awoken agent visits them, the Nine speak of two significant events. The first event is with expectation and appears to be Mara Sov's plan with her Techeuns. They are confident that her fall is inevitable for the odds she plays with have been weighted by them. The second event is tinged with overtones of regret and sadness; the Nine lament their slaughter of the remaining Ahamkara after Riven was taken by Oryx.[note 2] Regardless of the specifics, one member urges the rest to "rid [themselves] of regret".
During the Guardian's third visit to Mara Sov's throne, the Queen was seen talking to The Emissary, saying that she agreed with the Nine's terms regarding an "asset" to be stationed "beyond the grave of the First Fleet". She then told the Emissary to remind the Nine that she had shown enough patience regarding the matter. The Emissary leaves and Sov warns the Guardian not to get involved in the Nine's schemes, claiming that they never end.
At an unknown time after the curse was unleashed upon the Dreaming City, the Nine argued with The Emissary regarding her status as a pawn of the Nine, Mara Sov's plan, and an oncoming storm. During the conversation, the Emissary pointed out the fact that seemingly only five of the Nine were present, which the Nine admitted was true. 
During her surveillance of the Drifter, the Praxic Warlock Aunor Mahal recorded at least one conversation between the Nine and the Drifter. The Drifter appeared to be speaking aloud to empty air, and remarked upon the Nine showing him visions of a future universe consumed by Darkness, as well as another vision of a universe suffused with Light. The Drifter rebuked the Nine for trying to sway him to their cause, upon which they apparently attempted to kill him by overheating his brain. The Drifter responded by using his Light to counter their attack.
In addition, one can hear different members of the Nine speak directly to the Emissary during several invitations of the Nine.
During Season of Arrivals, the Prophecy Dungeon was released. Here, Guardians accomplish various tasks given by the Nine in hopes of receiving an audience with them. In this audience, Guardians seek to understand the nature of the Darkness, to the best of the Nine's ability in describing it. The answer to this question is given by the Emissary on behalf of the Nine.
The answer was interpreted by the Drifter as the Nine stating that the difference between the Light and Dark was ultimately meaningless. Along with their answer to the player's question, they also foretold of the use and balance of Darkness in Stasis, the disappearance of Mars, Mercury, Io, and Titan, the Guardian's inevitable clash with Eramis, Kell of Darkness, and a at the time Unknown Cabal Threat.
For a very long time, little about the Nine or the Jovian peoples was known for very long due to their enigmatic and secretive nature. In Destiny, a Grimoire Card, Ghost Fragment: Legends 2, presents nine legends that offered contradictory clues and hints as to their nature. While these legends do not accurately describe the Nine, many of them accurately describe existing concepts or entities connected to the Nine, though the nature of the connection varies. The Emissary claims that both deliberately seeking the Nine out and doing nothing may lead one to encounter them, as they are "everywhere and nowhere". The Cabal call them the Ennead, and characterize them as "trapped and reaching out".
In Destiny 2 there are seventeen Lore entries from which can be gleaned five particular members of the Nine based on the writing style, with a potential sixth and seventh. It should be noted that VI could be I speaking more, and VII a possible typo, and thus not conclusive or definite.
These members are as follows:
The Nine also seem to have a connection to the Awoken or Ahamkara, as they were greatly angered by Oryx's incursion into the Dreaming City, and were driven into a frenzy when Riven was taken. In addition, the Techeun Shuro Chi believes that the Ahamkara either originated from or were sent by the Nine.
Agents of the Nine
List of appearances