The base has a rather complex layout, as it can be customized as needed due to their possession of a Mother Trigger. This is seen most of all by Kinuta reinforcing the walls after Chika fired through the wall with an Ibis rifle. Corridors connect ajoining rooms large and small, including the Operator Rooms, the Holo-Display room, the Sniper Range, and more.
Since Izuho brings her cat in there and Yōtarō brings Raijinmaru, it's clear that animals are allowed in the building.
Solo Rank Wars Booths
Used by various agents of all ranks, these virtual simulation rooms allow a safe space to train and refine your skills. Hyuse complimented the technology, suggesting it's Border-unique; or at least, Aftokrator does not have it. Booths can be accessed through a common area featuring large screens tallying the day's match-up's.
Each squad has their own operator room, or strategy room (C-rank squads dont't count as official squads, so Kōda Squad don't have one). A-Rank Squads have more space (complete with a kitchenette) and therefore more ability to customize their Operator rooms. When agents bail out, they typically head to these rooms that are equipped with beds to fall onto, although not all of them are at HQ, namely the branches. If they bail out inside the base, there are a series of vents that will take them to the Operator room of their squad which is mainly used during Group Rank Wars.
Holo Display Room
The room seen when the higher-ups meet with Yuma about information on the Neighborhood, where they have a holographic projection of the map of the Neighborhood. It is currently unknown if they ever use the projection for anything else, but it's set up so that there are rows of seats on three sides, with the holo projector in the center. Due to Replica's update, it houses a great deal of information gathered by Yūgo Kuga, Yuma's father.
Considered the largest room in the base, it's where Snipers, especially the trainees, go to train and rank up. It's also where Chika blew a hole in the wall firing an Ibis.