The Crown Bunker (unofficial) was an underground bunker located in the middle of the Wastelands in Vacuo, near a CCT relay tower. It served as a secret hideaway and throne room for The Crown, and where its army hid.
The Crown's Bunker was an underground facility deep beneath the Wastelands, a large desert in Vacuo. The entrance of the bunker was hidden deep underground, buried beneath the desert sands near a CCT relay tower.
Inside, four paths go towards the cardinal directions. Over time, the south cave had collapsed, but there's still three choices, north west and east. These hallways were dark and dimly lit.
The easternmost room led to a stone-carved throne room which Gillian Asturias used as her base of operations. Beside this was a large, disturbing hidden room which housed various beds which host bodies that were used by Gillian Asturias as Aura batteries.
The bunker was destroyed by a natural fire Dust crystal explosion, with the exception of one entrance.
Sometime before the novel, The Crown acquired this bunker and carved a stone throne room into it. They prepared a room to store Aura vessels so that they could ready their army.
After Fox Alistair appears with a support team consisting of Nolan Porfirio, Octavia Ember, and Sage Ayana to rescue Team ROSC from the Grimm, he tells them of another underground Crown base nearby near a pirated CCT relay tower. Fox and Coco Adel realize the base is likely beneath the sand, and that Carmine Esclados would be the one to know the entrance. Instead, Coco decides to use her Semblance to blast her way through the sand to find it.
Nolan stays behind to keep watch as they enter the narrow underground bunker. The team sees a split in the bunker, leading to different routes. They hear voices from the east: the direction of Vacuo city. Fox senses the Aura ahead, and finds it to be the source of the identical Aura he's been sensing.
They hear Rosa Schwein talking to a woman named Gillian in the caves, who tells her that she should take all of it since it is war. Gillian nearly snaps when Rosa uses a Scroll in front of her, though Rosa retorts they need to use a Scroll to get by.
As Gillian steps up from her throne, she enters a room filled with sleeping people, draining their Aura for herself. As the group realizes her Semblance, they also sense Bertilak Celadon in the room amongst the bodies. Gillian tells Rosa to bring her army into the room, as a large group of silver-armband armored men enter, including Argento Pocoron. The group decides to retreat in order to live.
Velvet Scarlatina, Octavia Ember, and Sun Wukong later enter the bunker to find Gillian and Carmine Esclados. They find it mostly abandoned, with the exception of the Aura vessels waking from their sleep. Sun helps them whilst Velvet and Octavia continue to search for the Crown's leader, and eventually come across Gillian and Carmine. When Carmine begins to engage Velvet and Octavia, Gillian orders her to retreat, and the two begin to carve a new path out of the bunker. They come across a red fire Dust crystal, which Octavia blows up to attempt to kill Carmine and Gillian. Most of the bunker is buried in rubble, and an awoken Bertilak Celadon helps the Huntsmen and victims escape without any injuries.