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This article is about the cut Halo 2 campaign level. For a list of starships employed by the Covenant, see Covenant starship.
Covenantship was the working title for a level intended to be featured in Halo 2. The level would have taken place immediately after Cairo Station, and involve the Master Chief's efforts at blowing up the CAS-class assault carrier Day of Jubilation from the inside via boarding. The level was ultimately replaced in the final game with the famous cutscene in which the Chief launches through space with a Covenant bomb to blow up the carrier instead.
Covenantship was cut fairly early on in development, and replaced with a cutscene that created "just as much work" for the development team. The level was to involve the Master Chief boarding the eponymous Covenant spacecraft and lead a boarding action alongside a group of ODSTs and Miranda Keyes. The level would end with the Master Chief using a Wraith tank to blow up the ship's pinch fusion reactor - notably serving as the first introduction to the ability to drive the Wraith in the series. The level would have also served as the main introduction for Miranda, who would spend a significant chunk of the level fighting alongside the player.
A layout whiteboard briefly featured in the Designing the Levels featurette bundled on the Halo 2 Limited Collector's Edition disc seems to match up with many of these details, and illuminates more about the level's intended structure. The whiteboard shows a backdrop appearing to look like the upper hull of a Ket-pattern battlecruiser or CAS-class assault carrier against a backdrop of stars, and features Master Chief and mentions of ODSTs jumping between alternating "trains", alongside fighting Grunts. Mid-way through the mission a note about "skybox dialogue" is mentioned, possibly indicating the ongoing space battle around Earth. The players would eventually be blocked from proceeding further by a blockade, leading to a lighting change. Other details on the board are too obscured in the shot to make out fully, though seem to reference the aforementioned Wraith near the end of the level and curiously, a Scarab walker. The context surrounding the Scarab is unknown.
A final detail on the whiteboard on the right-hand side mentions Ghosts from behind - indicating at a certain point the player and their team may have been intercepted by Ghost attack craft - a detail which lines up well with several of the storyboards featured below.
A number of storyboards intended for this mission were posted online by Lee Wilson in 2020. The storyboards showcase two alternating takes on the mission's opening cutscene, both different to that featured in the final game.
In the cutscene's intro, the Chief largely falls down away from the camera in the same way he does in the announcement trailer and Cairo Station cutscene. Notably at this time, the idea of the assault carrier didn't exist yet, so the ship is represented by a standard Ket-pattern cruiser. The Master Chief lands on the ship's hull and climbs inside a trench inbetween sections of armour plating, ultimately coming up to a maintenance airlock and opening it to find a group of Drones - who rush the Chief and gameplay begins.
The next set of storyboards then showcase the Master Chief's escape from the carrier by flying out of the ship on a Ghost, before jumping out of the Ghost and falling into Sgt. Johnson's Pelican drophsip. The destroyed carrier falls to Earth and crashes into the city below.
These second iterations of the covenantship cinematic more closely resemble that found in the final game - the primary differences come from the fact that there is still no antimatter bomb. Additionally, after the Marathon-class heavy cruiser is blown up by the carrier, the bombing run sequence is altered; rather than the Longsword fighters used in the final game, this sequence features a wing of strike fighters (a cut vehicle) supporting the Chief and bombing the Covenant point-defence turrets (represented by the large anti-air gun first seen in the Halo 2 E3 demo and later reused for the Zo'op-pattern Weevil artillery in the final game). The Chief lands on the ship at the reactor. The storyboards cut off here, so what was intended at this stage of development is unknown.