Bioweapon Research Center
The Bioweapon Research Center, reached from an elevator in the Biosphere, is the last area Samus Aran explores on the Bottle Ship before leaving the facility for the first time. Initial exploration is limited to a single room, which features an array of computers in the center. From these and MB, who is masquerading as Madeline Bergman, Samus learns the details of the bioweapons plot uncovered earlier in the Exam Center and learns of Project Metroid Warriors, a plan focusing on the propagation of Metroids as bioweapons, deemed more important than the other organisms in the facility. After Samus leaves to explore Sector Zero, the Deleter appears from behind a staircase and attacks MB. When Samus returns, MB is gone, and the room is empty save for the corpse of James Pierce.
During Samus's later visit, the Research Center is far less peaceful. Sentry drones populate the corridor leading to the room explored previously, and an adjoining room contains a plethora of Super Zebesians. In the bowels of the Research Center, accessed via another elevator, is a chromatic chamber, in the corner of which is the dried husk of Ridley. Further on, passage through subsequent corridors is impeded by Rinkas and a small number of Blast Shields on the doors. Eventually, Samus reaches Room MW, the largest room in the complex. It contains six large specimen tanks, holding cells along two of the walls, and a large hangar-like door. The real Madeline Bergman is encountered in one of the holding cells, and in a state of panic upon being sighted, she releases the Queen Metroid, which is fought here. Madeline then runs, and Samus pursues her, calming her down and learning from her the truth of the situation on the Bottle Ship before both of them are confronted by MB, who assaults them and Galactic Federation soldiers with Desbrachians. Samus is escorted from the Research Center by Anthony Higgs following MB's demise.
- "CONFIDENTIAL/TOP SECRET
Metroid Militarization Plan
(PMW: Project Metroid Warriors)
Concerning the feasibility of Metroids as military bioweapons." —Bioweapon Research Center computer (Metroid: Other M)
- "If the situation were left alone, galactic society would be put in peril. Even the ringleaders of the operation wanted to avoid that, but they still wanted the Metroids." —Samus Aran (Metroid: Other M)
- "They decided to capture the Metroids contained in Sector Zero... and "delete" the rest of the facility, including the Space Pirates, Ridley, and everyone who knew the secret." —Samus Aran (Metroid: Other M)
- "Time for us to go. C'mon, Princess." —Anthony Higgs (Metroid: Other M)