Damien's tower is completely underground but above ground he has made large dome shaped building. In this building there is a gym, sparring area, basketball hoops, volleyball courts, a track, a spa, hot tubs, pools, a sauna, and food court which is stocked with human food and alcohol and run by hollows that serve Damien. This whole building is open to anyone.
Outside the tower there was a huge sliding metal door over the top of the tower that had a huge number 8 on it. There is a dna scanner next to the metal door and all vistors would have to put there hand on it before they are granted access. Once granted access the sliding metal door will open and reveal a floating platform. You stand on the floating platform and you can go down to the 1st basement level only.
1st Basement Level: The platform drops you off here. There is nothing here besides the beginning of the winding steps and ape like hollow guards.
2nd Basement Level: Marco's floor.
3rd Basement Level: An ecosystem where Damien's pet crabs live. There is only sand and water on the floor.
4th Basement Level: Jimi's floor.
5th Basement Level: Rhaegar's floor
6th Basement Level: Dorin's floor
7th 'Basement Level: Eligor's floor
8, 9, 10th Basement Levels: Empty floors.
11th Basement Level: Damien and his fraccion's personal training room.
12th Basement Level: Multiple rooms. Water room. Heat Room. Forest Room.
13th Basement Level: Where Damien's ape like arrancars guardians stay.
14th Basement Level: Damien's floor. The only part that is seen is the front room where Damien has a dining table, and his own personal throne.
15th Basement Level: Secret floor that no one knows about besides Damien and the apes who made it, he killed those certain apes after they finished.