Hijacking Alterra Communications - Subnautica: Below Zero Guide - IGN (2024)

Welcome to IGN's Subnautica: Below Zero walkthrough. This section will teach you how to Hijack Alterra Communications for Marguerite.

To begin, you will need a few pieces of equipment, including the Laser Cutter.

Building a Laser Cutter

The Laser Cutter requires Crystalline Sulfur, Titanium, a Battery and Diamond. You will have previously discovered Diamond by Finding the Koppa Mining Site.

You must also scan three Laser Cutter Fragments, located in the Sea Monkey Nests in the Artic Kelp Caves. You should have dropped a Beacon here previously, but if not, feel free to visit the Building a Compass section of the Finding Delta Base page for instructions.

However, this time you will need to follow the caves much deeper to find the Nests, up to 150 meters.

The Sea Monkey Nests are common, but there are multiple types of fragments. You'll need to visit several to find all three Laser Cutter Fragments.

While exploring, you may also discover an Architect Artifact at about 150 meters. This will trigger a conversation with AL-An.

While exiting the caves be sure to collect some Crystalline Sulfur. This can be found in empty pods after the Exploding Fish have left them. Your Seaglide is faster than these enemies so simply avoid them and double back to collect the resource.

Getting the Parallel Processor Unit

Once you have the Laser Cutter you are ready to begin collecting fragments of the Parallel Processing Unit. You will need to find the Mercury II wreck in order to do so. Two of the three fragments are located inside.

From Delta Station Dock, head two clicks right of South. You will pass the Purple Vents. Continue down until you see the Mercury II wreck; it should only take a few seconds in your Seatruck.

At the bottom and back of the wreck you will find a hole that's perfect for parking your Seatruck.

Go up through this hole. Go across the hallway to the adjacent room. Look to your left.

You will see the first sealed door; cut it open with the Laser Cutter.

You will be able to scan the Fragment inside. Then, look directly above you. There will be a hole in the ceiling. Go through this hole and look directly ahead; you will see the next fragment.

Scan this fragment, too. Collect any Metal Salvage or other items nearby and return to your Seatruck when you are ready. We dropped a Beacon here so it is easy to return if you need to go back to your Drop Pod in between for food and supplies.

If you are ready to continue, however, you'll want to leave the Mercury II entrance and head two clicks right of Southeast and down to about 200 meters. In just a few seconds with your Seatruck, you will see the second of three of the Mercury II wreck pieces.

You'll look for a door on the right side of the wreck near the front that's nearly covered by Vent Garden roots (this is back in the Lily Pad Island biome).

Enter and turn immediately right through the Vent Garden roots near the staircase.

You will come to a sealed door and you will need the Laser Cutter to open it.

After this you'll be able to access a big main room. On the next level up and to the left you'll come to yet another sealed door you'll need to open with the Laser Cutter.

Inside this room will be a grow bed. To the left you'll see a vent; enter and follow the vent down and around.

On the wall you exit the vent from (so the wall directly behind you) you'll find the final Parallel Processing Unity fragment to scan. Do so and when you are ready, return home. Keep in mind you can stay and explore as long as you like, and you will find PDAs with information about the Mercury II crew.

Building the Test Override Module

The Parallel Processing Unit requires Gold, Silver and Table Coral, items you will have perviously collected from the Artic Kelp Caves, Koppa Mining Site or Twisty Bridges.

The Test Override Module, which you should have scanned while Finding Marguerite's Seabase, requires the Parallel Processing Unit, Titanium, Lead and Copper Wire. Lead can be found in Galena Outcrops, located in the Deep Twisty Bridges, Lilypad Islands and other locations—including Sea Monkeys, who may sometimes gift you items.

After you have built these items, travel to Delta Station Dock.

Once you've arrived head up the mountain path using Thermal Lily plants to stay warm. If you are traveling at night and have not made a Headlamp, you may use your Seaglide to light the way.

Follow the Light Stick path until you reach Delta Station.

Inside you will find many scannable items and PDAs.

If you leave the Station you will come to the Communications Tower at the top of the mountain.

Walk to the Communications Tower Terminal and select "Status Report" to upload this information to your PDA. Climb the ladder on the tower and hook the Test Override Module to the Tower.

Climb back down the ladder and return to the Terminal. Selected "Test Mode" to override the Tower and send the "All Clear," signal, which will take the satellite offline.

After this is complete, AL-An will tell you he impressed, and Marguerite will give you a call with coordinates to her Greenhouse.