- "It sure doesn't look like an elevator shaft."
- — Phi to Sigma, about the warehouse
Warehouse A is a huge room in Rhizome 9 where the AB Rooms and the Number Nine Door are located. The warehouse has Chromatic Doors in magenta, yellow, and cyan colors. These doors lead to escape rooms.
The room has six small rooms that look similar to elevators, called AB Rooms. Above the AB Rooms is a crane that can move them. It has a huge gate with "9" painted on it in red, and three colored doors leading to other rooms. They are magenta, yellow, and cyan. Next to the AB Rooms is a wall with a message written in red, "TWO MILKMEN GO COMEDY!", which is an anagram for "WELCOME TO MY KINGDOM!". The walls in the room are a grayish brownish color.
After escaping from the elevator, Sigma and Phi find themselves in a large warehouse room. They notice a group of people standing in front of a big metal door, and run toward them. The five people introduce themselves, and their names are Dio, Quark, Tenmyouji, Alice, and Luna, all wearing similar bracelets on their wrists. Every one of them was apparently kidnapped and woke up in the other elevator rooms.
After exchanging information, they realize that no one has come out of one of the six rooms, and as they wonder if anyone is still inside, the hatch on top of the elevator opens and a man wearing armor appears, carrying the unconscious Clover in his hands. The man later introduces himself as K, after Clover wakes up. Afterwards, Zero III explains the rules to the 9 players and they go through the Chromatic Doors.
Depending on the timeline, Dio either kills the old woman and hides the murder weapon, which is a knife, between the two leftmost AB rooms or plants the  bomb in the exact same place.
- When Sigma goes through the Cyan chromatic door, the leftmost AB room is not moved, as Akane did not die on that route.