Base Truck. Eighteen also sent over the internal 3D map information of the base, and, as expected, Ganymede IV was indeed built based on the blueprint of the Neptune class.
Theoretically, the primary function of the Titan Battleship is not to serve as command, nor to sweep in with Doomsday Weapons. Most of the time, this class of ships acts as a strategic military base that can be deployed to the front lines at any moment, providing repair and supply services for the Dreadnought Class main fleet, while also offering strategic deterrence with Doomsday Weapons when necessary, forcing the opponent to abandon their strategic intent to conserve fleet strength.
Of course, it's also apparent that Ganymede IV Base is very chaotic, with some areas under construction and others sealed off, large swathes of blank and restricted areas. It doesn't even have the basic functions of a military base yet.