Sector 4

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Sector 4 (AQA) was the aquatic area of the BSL Station. It housed various X Parasite infected creatures such as Serris, Sciser, Skultera, Owtch, Gold Sciser, Balloon Creatures, Evir, Mermen Pirates and Slickle.

By the time the player enters this area, the first section has been heavily damaged by an X Parasite mimicking Serris. A pumping station to control the water level in the main tanks is also present.

Sector 4 is made up of two areas: An upper area and a lower area. The upper area is more technologically advanced and is where you face Serris. The area also contains many tanks filled with water that are electrified due to broken wires. The computer will tell you that you can't cut the power because it would shutdown the station itself, and instead you must lower the water level using the controls in the pumping station. The lower area is completely under water so the Gravity Suit must be acquired before entering. This area had very little technology compared to the the upper area and resembles an ocean. This area is where you unlock the Level 4 security doors. It cannot be reached from the upper area, but can be reached from Sector 5 (ARC).