Subnautica: Below Zero is about more than simple survival. As players explore the seas and ice-flows, they will discover a series of mysteries that they can try and solve in the hope that each one will bring them a little closer to learning the fate of their sister. The ocean floor contains all manner of mysteries, from strange ancient obelisks to all manner of rare creatures and resources.

As players explore the world of Subnautica: Below Zero, they will occasionally see a beacon marking a specific area of the seabed. As long as players have already met Marguerit Maida, who first appears before they have to track down the Parallel Processing Unit, they will see a beacon that says "Pilot last known position" when they are near the Purple Vents biome.

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Players can find entrances to a cave system along the edges of the Lilypad Islands and Tree Spires biomes that border the purple vents. Heading to coordinates 102-366-922 will bring them to a secret sea base. To enter the base, players will need to swim down underneath it, coming up through the pool of water in one of the rooms. This is quite deep, and players will want to ensure they have plenty of oxygen when they start and top up regularly at the oxygen plants that can be found along the way.

The first thing players should do here is scan Marguerit's Prawn Suit. Then they can venture through the door where they will come face to face with Marguerit for the second time and her pet Snow Stalker. Once Marguerit is convinced that players are not working against her, she will be reasonably willing to give information as long as players can prove their worth.

The main room contains a Seatruck Perimeter Defense Upgrade, so players will want to ensure they pick it up before leaving. There is also a Snowfox vehicle fragment that can be scanned in the center of the room, a test override module that can also be scanned. Finally, players can even scan the pet Snow Stalker to add yet more information to their database.

It is worth returning to the base after players have disabled the tracking satellite tower that Marguerit wants them to deal with, as they will be able to get further into the base and scan more objects. There are no new modules or fragments, but players will be able to get blueprints for an assortment of different build items.

Subnautica: Below Zero is currently available for PC, PlayStation 4, PlayStation 5, Switch, Xbox One, and Xbox Series X/S.

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