Subnautica: Below Zero Codes and Tips

Make crafting the Survival Knife using the Fabricator in the Drop Pod one of your first priorities. The main function of the Survival Knife is to procure samples of certain corals and flora such as Table Coral Samples and Creepvine Samples. It can also be used as a weapon but it's damage and range are limited. To craft the Survival Knife you will need Titanium and Silicon Rubber which is made from Creepvine Seed Clusters which can be plucked from the middle of the Creepvine plants. Later in the game you can upgrade the Survival Knife to the Thermoblade by using the Modification Station.

The more oxygen you have in Subnautica: Below Zero the farther down you will be able to dive. This basically means in order to explore for longer you should prioritize collecting the resources needed to upgrade your oxygen tank. The resources required to make your oxygen tank are two Titanium and one Fiber Mesh. Titanium can be found by smashing the interactable rocks you find scattered around the sea bed, and you will need to use your knife to cut down the glowing red Creepvines that grow out of the ground to get the two Creepvine samples needed to make the Fiber Mesh.

Make sure when you go exploring you take a sufficient amount of food and water with you in order to help prevent the health bar in the bottom left corner of the screen dropping to zero. Allowing the health bar to drop to zero will result in your character dying and respawning in the base (except on Hardcore). Although this respawn will cost you a few items from your inventory, the game gives you the opportunity to retrieve those lost items by going to the place where you died.

At the start of Subnautica: Below Zero when you have a limited supply of oxygen it is important that you remember that you are in the arctic zone and the water's surface is covered by ice floes of varying sizes which will prevent you from resurfacing to replenish your oxygen supply. It is therefore important that you pay attention to how much oxygen you have remaining and where the ice floes are above you, so you don't get trapped and suffocate.

Listed below is a completion checklist of events and locations you can visit in Subnautica: Below Zero. Note: The list is full of spoilers.
Early Game (Part 1)

- Find the Drop Pod and acquire basic tools.

- Visit Sanctuary Zero and download AL-AN. Once acquired, you can complete the rest of the game in any order.
Delta Island and Surroundings (Part 2)

- Visit Delta Island, meet Maida for the 1st time, and explore Delta Station.

- Explore surrounding biomes: Thermal Spires, Lilypad Islands, Purple Vents, Tree Spires, Deep Twisty Bridges.

- Explore nearby abandoned sites: Omega Lab, Koppa Mining Site , Outpost Zero. Some of these are also related to Parts 2 and 3.
Story Events Related to Maida (Part 3)

- Meet Maida for the 1st time on Delta Island.

- Scan 3 fragments of Parallel Processing Units from the 3 Crashed Ships.

- Meet Maida for the 2nd time at her base and receive the Test Override Module blueprints.

- Reprogram the Satellite Tower

- Visit Maida at her greenhouse.

- Re-visit her underwater base.
Story Events Related to your Sister (Part 4)

- Explore the Omega Lab.

- Explore the Glacial Basin.

- Find Phi Robotics Lab (I.e. Snowfox Base) in the Glacial Basin.

- Visit Outpost Zero and the Architect Gate Base.

- Find the Kharaa Antidote in Spy Penguin Cave #3.

- Inject the Kharaa Antidote into the Frozen Leviathan.
Story Events Related to AL-AN (Part 5)

- Scan AL-AN's skeleton from the Deep Lillypad cache.

- Scan AL-AN's organs from the Crystal Caves cache.

- Scan AL-AN's tissues from the Arctic Spires cache.

- Construct AL-AN's body from the 3 body fragments.

- Visit the Architect Gate Base.
Optional Tasks and Locations

- Build Seatruck and Prawn Suit and their upgrades.

- Visit Koppa Mining Site.

- Find the Architect Artifacts.

You will have limited oxygen when you start out in Subnautica: Below Zero so do not be tempted to explore any deep chasms you find straight away as you will not be able to resurface in them and get oxygen. Hold off from exploring the deeper caves until later in the game when you have upgraded your oxygen tank and Seaglide vehicle so that you have more oxygen and easier movement.

Every time you see something new in Subnautica: Below Zero you should try scanning it. Whenever you scan something it gives you information and helps unlock construction blueprints. It is important that you unlock construction blueprints as the game is equipment-gated from the very start, so you will find it very hard to survive in certain places unless you have the appropriate equipment. Read the PDA for everything you scan as it often give hints about how to use them.

The resources that you can harvest in Subnautica: Below Zero are generally difficult to see and can be easily missed which is something you want to avoid happening. You can make resources easier to spot by adding a colored outline to them by opening the menu, going to 'Options', and checking off the 'Highlight Interactable' box under 'Accessibility'.

Like it's predessor, there is no in-game map or mini-map to rely on in Subnautica: Below Zero. This means you will need to map out your surroundings in your head using your central Drop Pod as your landmark. If you feel overwhelmed doing this you can take a look at the player-made map below to see where everything is, but it is recommended that you resist the temptation of doing this for as long as you can as a big part of the appeal of the Subnautica series is mapping out your surroundings.