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The Pyramid is the name used by Eris Morn and the Ghost to refer to a seemingly derelict Pyramid located below the surface of the Moon. This being is a part of the aforementioned fleet that attacked the Sol System during the Collapse, which are synonymous with the Darkness. It is the main antagonist of Shadowkeep.
Overview and layout
The outside of the Pyramid's hull is covered in segmented panels that vary in pattern, with some having vertical lines and other with patterns resembling circuitry. Much like the Traveler, the surfaces of the Pyramid seem to be composed of some form of rock-like material, occasionally having an uneven or chiseled appearance, giving the ship an almost handcrafted quality.
The Pyramid can be accessed by an opening on one of its upward-facing sides; this opening can produce a tractor beam to bring objects or visitors inside. The interior of the Pyramid appears to have been designed with human-scale inhabitants in mind and contains many hallways, stairways, and various open spaces. Many parts of the architecture feature subtle gold ornamentation or chiseled, seemingly abstract patterns. It is dimly lit, with occasional harsh white or red lighting providing the only illumination. Small container-like objects can be found scattered around the halls.
Among the most notable objects found within the pyramid is a massive sculpture, apparently of a humanoid figure draped in what appears to be a veil or shroud. It is currently unknown what this sculpture represents. However, a nearly identical one appears in the Black Garden, watched over by a Pyramid Scale and the Sanctified Mind, Sol Inherent.
The Hive under Crota, Son of Oryx were the first to discover the inactive Pyramid beneath the Moon centuries ago which lead them to embed themselves into the planetoid as a War moon. It is implied by Toland that the Hive had studied the dormant structure and failed to awaken it countless times before the events of Shadowkeep.
Under the leadership of the Daughters of Crota, the Hive built a Scarlet Keep near the Pyramid's location that could amplify their magics, harness the phantasmal essence of the Pyramid and immunize themselves of its influence. In addition, the Daughters attempted to use the Nightmare essence to recreate Oryx, the Taken King and their father Crota to no avail.
The Pyramid was discovered by Eris Morn following the Red War and the events of Forsaken. Upon touching its surface, Eris apparently triggered a seismic disturbance, revealing the Pyramid in its crevasse. Having awakened by Eris, the sudden release of the Pyramid's potent energies leveled the terrain of the Ocean of Storms and subsequetly brought Nightmares in the form of phantoms, which haunted the surrounding caverns and lunar surface.
The Hive of the Hidden Swarm saw a prime opportunity in the Pyramid's sudden appearance and of its phantasmal creations. Under the leadership of the Daughters of Crota, the Hive began summoning Nightmares near the Keep starting with the Nightmare of Gothrax, Swarm Protector and the Nightmare of Arguth, the Tormented. Eventually, they began to summon Nightmares en masse and sacrifice them to reap their phantasmal essence to empower Zulmak, Instrument of Torment; a hybrid Hive-Nightmare abomination to serve as the Daughters' puppet champion.
After crafting a set of Dreambane Armor with the aid of Eris Morn, the Guardian was able to approach the Pyramid, which produced a tractor beam to draw the Guardian inside. Within the Pyramid, the Guardian faced Nightmares of Ghaul, Fikrul, and Crota. The Guardian's Ghost was seemingly possessed by the Darkness during this period and commented on the weakness and failures of the Light. After slaying the Nightmare of Crota, the Guardian was guided to a statue of a veiled figure with an unknown artifact placed before it. The Guardian hallucinated themself in the Black Garden, where a doppelganger with a sinister smile spoke on behalf of the Pyramid.
Sometime later in the season, Eris herself would personally step into the Pyramid and approach the Veiled statue as well. Upon touching its base, the Darkness-aligned powers of Stasis began manifesting temporarily around her rock much to her surprise. Taking this development of wielding the Darkness under her control, She resolves to accept these newfound powers from the Pyramid as her own.