BSL Sector 4

A map of the BSL Station's Sector 4. Includes all item and boss locations.

Sector 4 (AQA) was the aquatic area of the Biologic Space Laboratories research station. It housed various X Parasite-infected creatures such as Serris, Sciser, Skultera, Owtch, Gold Sciser, Powamp, Evir, Space Pirates and Yard.

Sector 4 was made up of two areas: an upper area and a lower area. The upper area has large amounts of advanced technology and is where Samus faces Serris. The area also contains many tanks filled with Water that are electrified due to power nodes broken by Serris. The computer tells Samus that the power should not be cut because it would shut down the entire station and greatly hinder her attempts to combat the X. Instead, Samus must lower the water level using the Pump Control Unit.

BSL AQA Screen1

The terrain in the lower part of the sector is very similar to one of Earth's oceans.

The lower area is completely underwater, so the Gravity Suit must be acquired before Samus can explore it fully. This area has very little technology compared to the upper area and resembles a coral reef. This area is where Samus unlocks the Level 4 security doors. Samus cannot reach this part of Sector 4 from the upper area at first and therefore arrives by going through Sector 5.

Power UpsEdit

Main article: Sector 4/Items


Metroid - Fusion 15

Clams are abundant in the scenery.


Official dataEdit


"Sector 4 is used to research marine creatures."


"Sector 4 has been constructed to support a delicately balanced water habitat."