Terran Valhalla

The mighty Valhalla is not available in a vanilla game, but present in the game files. This behemoth is canonically the flagship of the ATF, boasting large weapon arrays, spacious hangars and massive shields. It is also one of the largest craft in the game, being too wide to fit through gates. It is obviously unfinished, as there are also some turret placement and targeting bugs in its design. Its hangar can accommodate Medium-sized ships, a trait shared by the Aran, Ozias and several M7C class ships..
In the literature, the Valhalla is classified as an M0 Battleship, but as there is no actual M0 classification in X3: Terran Conflict, it appears in-game as an M2 Destroyer.