A large structure that shadows over the white sands located within the outer regions of Hueco Mundo. In these regions are where the natural born hollows. Beings who haven't descended from human souls, but who were born as hollows just as the shinigami born souls of the court of pure souls in Soul Society. This tower like headquarters extends for miles into the far reaches of the skies where the Vizards have a wide field of vision over a large expanse of everything taking place in Hueco Mundo. Here the four Overseers including the Imperator can be found during many the meetings of the army of Masks. The skyscraper like building ranges from approximately 100 floors, however the length betwee each floor ranges in the measurement of miles and it can take days to get to the top for those foreign to the tower. Those who have their names placed on the Tabula Nocturna have no trouble through it. Surrounding it are the four Army of Mask towers representing the castes.