Borg sphere
From Tardis Wiki, the free Doctor Who reference
The Borg sphere was a type of huge sphere-shaped starship used by the Borg. They were part of the fleet of the Borg-Cybermen alliance along with Borg cubes and Cyber-ships. (COMIC: Assimilation²)
Behind the scenes
The Borg sphere is, after the Borg cube, the most common type of Borg ship to be seen in Star Trek, having appeared in the movie Star Trek: First Contact and various times in the spin-off series Star Trek: Voyager. In-universe, their appearance in Assimilation² takes place years before their on-screen appearances. In First Contact, the Borg sphere demonstrates the ability to time travel, fulfilling the ambition that the Borg make at the end of Assimilation².
