Keyship

Keyship is a classification of superluminal Forerunner vessel in use at the time of the Long Night. Keyships were capable of activating slipspace portals leading to the Ark. Though many more once existed, the majority were destroyed by the Librarian to prevent the Flood from reaching the Ark.
== Specifications ==
=== Superstructure and hull ===
Like most other Forerunner constructs, keyships are geometric and angular, possesing a tetrahedral spaceframe, with a forward triangular prow, and three similarly shaped struts attached to it at equidistant points, to help ground the ship. Visually, their hulls are gray in color. keyships are estimated to be14,000 meters (8.699 miles) tall at a minimum and are far heavier than most civilian spacecraft, but are still significantly outmassed by a variety of transport and military vessels.
=== Power generation and propulsion ===
=== Armament and defenses ===
Although their weapons systems are unknown, one keyship was found and used by the san'shyuum Reformists during the War of Beginnings, and was far superior to sangheili vessels of the time. The same keyship's shielding was completely impervious to even the heaviest of shipborne armaments. A keyship has been known to carry over 1,000 beings, which is believed to be only a fraction of its full carrying capacity. They were capable of remote detonation to prevent their usage by the Flood.
== History ==
The keyship was originally designed by naval architects Grasping-Steady-Firmament and Lightning-Weaving-Helix and manufactured by the Ingens Assembler Vats. The vessel was intended as a multirole spacecraft, combining speed and agility with robust modularity, it was used extensively by both the Warrior-Servant and Lifeworker rates.
=== Long Night ===
During the Long Night, the Forerunners extensively used a fleet of Keyships. A number of Keyships were given to the Librarian, and combined with a number of slipspace portals leading to the Ark, the Librarian was able to transport herself back to the Ark with her Keyships if the situation required. The Librarian eventually destroyed her Keyships to prevent them from falling into the hands of the Flood, who with them, would be able to instantaneously travel to the Ark, rendering the Halo Array useless. This action stranded the Librarian on Erde-Tyrene, within the lethal range of the Halos.
Near the end of the war, the Keyships were part of an unknown strategy to hold off the Flood for nearly 79 years, although this advantage would be foiled by the massive computing power of the Flood.
=== Key to repopulation ===
Keyships were also an integral part of the Forerunners' Library Project to preserve sentient life. Before the firing of the Array, the Forerunners gathered DNA and living specimens of the notable sentient species located throughout the galaxy and protected them from the devastation of the Flood and all other life via Halo by transporting them to the Ark. After the seven ringworlds fired out their pulses, several keyships, containing preserved specimens of each species, were sent to the planets from which the sentient species originated, and released a population of the species on their planet of origin.
=== Legacy ===
Mendicant Bias would find his way onboard a keyship Anodyne Spirit to Janjur Qom. No Keyships were to be left on indexed worlds according to the Forerunners' plan, leaving this particular instance a curious anomaly. That particular vessel, referred to by the Covenant as the Forerunner Dreadnought, was most probably one of, if not the last surviving Forerunner keyship in existence, used by the Covenant as an unusual source of power for their holy city, High Charity. At the end of the Ninth Age of Reclamation, the Prophet of Truth appropriated the dreadnought to travel to Installation 00.