Carolus Patricius: (カロルス・パトリキウス, Karorusu Patorikiusu?) is a Noble Phantasm of Karl der Große. The St. Metropolita itself. A giant flying fortress that, by its nature, expands constantly to cover the area beneath it. Due to its size, it essentially qualifies as its own territory. Its material also composes Karl's personal armor.
Patricius was originally a title given to guardians of Rome and Italy, and means "fatherly protector". It is known to possess several defense emplacements known as Karl Cannons for long-range bombardment, as well as at least two Facsimile Servant Creation Facilities to create bootleg Servants from the mana of Gilgamesh and Jeanne d'Arc. It also has a Cathedral-like Throne Room where Karl der Große is faced during the final battle of each route's ending. Another area of note is the location of the Monolith (異星鍵, Isei Kagi?), placed at an unspecified spot within it's territory.