The last of it's new features is an underground chamber which is the same size as the above ground fortress. The "ground" of this chamber is made of sekkiseki, but is covered by desert sands so that it is unnoticeable. It resembles the Menos Forest in the outside Hueco Mundo with small huts and spires that are used as living quarters and meeting halls for the Eximo Espada, who assist the Los Cinco Dios in their goals. It also has a hidden spire, disguised as one of the quartz trees of Hueco Mundo, that connects to the upper Las Noches and one secret passage, that leads to the dunes of Hueco Mundo.