Similar to Darth Vader's Executer Star Destroyer, the idea here is that this was the command ship for the Kreed Maykr, also known as Bishop Kreed. This would have eclipsed all other Maykr ships near it as well as other craft. A sign of his 'opulence' the early sketches and iterations often incorporated his face or other ego driven designs.
Art Direction: Emerson Tung https://www.artstation.com/emersontung
Exterior Model and more by https://www.artstation.com/artwork/XJVXXy
All Images © id Software, Zenimax Media Inc.