Subnautica 2 Temperature & Radiation Guide : How to Survive Extreme Biomes
Heat, cold, and radiation kill you in specific zones. Here is how to survive each one, what gear you need, and which biomes require protection.
- •The Hydrothermal Vents need Heat Tolerance. Get the Angel Comb in the Blighted Area first. Clear Bloom Cankers with Sonic Resonator.
- •There is no cold protection yet. The deep ocean is cold but not lethal. Bring a heated knife if you get the blueprint.
- •Radiation zones are not in the current Early Access build. If you see radiation warnings in old guides, ignore them.
Certain biomes will kill you just by being there. Not predators. Not oxygen. The environment itself. Here is how to not die to water temperature.
Heat zones
Hydrothermal Vents (50-150m)
The water is hot enough to damage you. Constantly. You cannot stay here without Heat Tolerance.
Get the Heat Tolerance Adaptation from the Blighted Area Angel Comb. The Blighted Area is east of Old Habitat. Bloom Cankers block the entrance. Clear them with the Sonic Resonator.
Once you have Heat Tolerance, the Vents become safe. Gold and Sulfur are only here. Plan one dedicated expedition to clear out the resources.
Hot Caves (under Tailings Village)
Same heat. Same requirement. Infinite thermal power if you build a base here.
Cold zones
The deep ocean is cold. Below 200 meters, the water temperature drops. But cold does not kill you in Subnautica 2. It is uncomfortable. It is not lethal. You do not need cold protection.
If a guide tells you to craft cold-resistant gear, it is for Subnautica 1 or Below Zero. Not this game.
Radiation
Radiation zones do not exist in the current Early Access build. The Aurora reactor meltdown was Subnautica 1. There is no radiation in Subnautica 2. Ignore radiation warnings in old guides.
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This guide was compiled from multiple public sources. We cross-reference with 3+ sources before publishing.
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