Ascendant realm

"Whispered lore and fragmentary theories suggest that Crota represents a distinct class of Hive entities, not resident in our material world. My latest synthesis of this scattered esoterica suggests that Crota's 'home' is a universe created or remade by his power and occupied by Hive organisms of immense age."

- Ikora Rey The Ascendant realm (also known as the Ascendant Plane, Netherworld, Overworld, or Sea of Screams ) is a universe or alternate reality related to the Darkness. Entities closely linked to the Darkness, most notably powerful Hive such as Oryx, Savathun, Xivu Arath, or Crota, create "cyst universes" within the Ascendant Realm known as throne worlds, where they have absolute power over it through the Sword-Logic. The Worm Gods, a higher group in the Hive pantheon, also dwell in a deeper part of the Ascendant realm, much closer to The Deep.

Unknown Space, a location controlled by the Nine, is also located within the Ascendant realm.

Characteristics
Green-black "suns" are mentioned to be within the Ascendant Realm.

The development of a personal throne world is the natural result of reaching a certain level of power under the sword logic. All laws within these realms obey that logic, even other paracausal forces, such as the Light. They are typically formed and can grown in size by the deaths of powerful entities, including the Light-affiliated Guardians. They are completely immune to the effects of paracausal weaponry, such as the Harbingers of the Awoken, being spiritual worlds created from the mind of their resident god. If the god is killed, they persist still as all Throne Worlds are located and connected on the Ascendant realm's plane.

Throne Worlds have a connection to the Deep, the Worm Gods naturally living close to that connection while Oryx built a pathway and altar to communicate. If one of the Hive Gods is slain in the material world, or in another god's Throne, their soul will pass to their throne where they will regain their strength until they can re-enter the material world; this can potentially be accelerated by the sacrifice of lesser Hive. If they are killed within their own throne, they will die permanently. The lesser Hive may enter the Ascendant realm at will, but only if they are Ascendant Hive, those Hive warriors who command legions of lesser soldiers and can pay a tithe of death and destruction to the Hive god who rules them.

The Hive are not the only entities capable of forming a throne world. Hiraks, the Mindbender is an unprecedented Ascendant Fallen, as he fell into the Hellmouth as a Dreg and somehow gained Ascendant status, forging his own Throne within the Ascendant realm by means of Cayde's death. Other means of invading the Ascendant plane separately from the Darkness exist, as evidenced when the Harmony wishful bishops "wrestled" with Xivu Arath near her throne.

The Ascendant realm can also seemingly pull locations in our world into itself as well, as it did with the Dreaming City. Asteroid 128 Nemesis within The Reef also phase shifts between our world and the Ascendant realm, due to experimentation upon it by Hiraks, the Mindbender.

During the Taken War, Mara Sov also created a Throne World known as Eleusinia with Eris Morn's knowledge of the Sword Logic and through Riven's wish-magic; showing the possibility to built a throne world for the Light. However, it was corrupted by Oryx following her death in the Taken War, and is now a lair for Dûl Incaru, the Eternal Return where she is staging the Taken invasion of the Dreaming City.

History
"For you are not the first hero—nor even Oryx the first villain—to meet upon this plane."

- Sins of Kharad-Tan

Auryx was the first among the Hive to discover the Ascendant plane when Savathûn killed him for negotiating with the Ammonites, and the first to realize the innate power it held when the Worm Gods told him to slay his Hive and observe how his relationship to baseline reality began to change. These realms would prove to be a boon in the Hive's quest for immortality as they warred amongst themselves to deepen their power and understanding and during the war with the Ecumene, these realms gave them a place in which to recover.

During the war with the Ecumene, Auryx and his sisters were on the verge of defeat, and so met in his throne world to find a solution; Auryx then killed them after in order to gain the necessary strength. He then traveled the Ascendant plane in search of the Worm God Akka, to take the power needed to save himself and the Hive. Oryx would later return to explore the Ascendant plane more, trying to unlock the secrets of The Deep. He would later move his throne world out of the Ascendant realm when he built his Dreadnaught, turning it inside out and pouring it into the material plane.

There have only been six recorded events in which these realms were breached: once by the Vex; once by the Harmony's wishful bishops; and four times by the Guardians of Earth. The Vex were let into the High War by Savathûn tricking her nephew and proved difficult to defeat, mainly because of Quria, Blade Transform. Later the Harmony wishful bishops stalemated with Xivu Arath until her sister came to her aid. Finally, many years later, Crota's own realm was breached and the God-Prince killed; and Oryx's was invaded twice by Guardians, who first destroyed his material form and later faced his true form, once again vanquishing him, save for his heart, in which he continued to exist. Guardians also breached the Oversoul Throne a second time to steal a piece of Crota's soul. The sole exception is Toland, the Shattered; instead of breaching it, Toland was allowed to enter the Ascendant plane by Ir Yût, who did so by killing him with her Deathsong. This gave him greater insight into the Hive, but his true purpose was to search for Osiris.

At some point, Hiraks fell into the Hellmouth, surviving and learning to harness the power of the realm for his own purposes. He later used the power to pull Asteroid 128 Nemesis between our world and the Ascendant realm.

Despite Oryx's defeat, a number of worrying reports during the Red War indicate that something is trying to communicate from the Ascendant realm to scattered Taken forces on Io.

At an unknown point, the Dreaming City was pulled into the Ascendant realm, trapping it in a perpetual state within both the realm and our world.

Known Throne Worlds & Locales

 * High War—realm of Oryx; converted into the Dreadnaught.
 * High Coven—Savathûn's realm.
 * Xivu Arath's realm.
 * Ascendant Plane (Tangled Shore)—the space between throne worlds, also realm of Hiraks.
 * Oversoul Throne—realm of Crota.
 * Dreaming City—an abandoned City that is the most sacred location of the Awoken race. Warped by a Taken curse, it remains in-between the real world and the Ascendant realm.
 * Asteroid 128 Nemesis—experimentation by Hiraks, the Mindbender led to this asteroid being repeatedly pulled between the Ascendant realm and our dimension.
 * Unknown Throne World—discovered by Eris Morn, created for a being aligned to the Light.
 * Eleusinia—third throne world of Mara Sov, created shortly before the Taken War and later desecrated by Oryx, the Taken King.
 * The Haul—a pocket subspace of the Ascendant Plane gifted to the Drifter from the Nine, used to keep his Taken army caged and to test Guardians during The Reckoning.
 * Unknown Space—a domain of the Nine located within the Ascendant Plane.

Trivia

 * The capitalization of terms used for the Ascendant Plane is highly variable. The Ascendant Plane may be written as the Ascendant plane or ascendant plane, for example.
 * Throne World creators seem to be able to change the size of themselves within the plane, such as Oryx or Hiraks.
 * Since both Hiraks and Oryx appear bigger within their respective throne worlds, it might be that they are in their true size, and that they are in fact making themselves smaller when entering the material world.

List of appearances

 * Destiny
 * The Dark Below
 * The Taken King
 * Destiny 2
 * Forsaken
 * Penumbra
 * Shadowkeep