Subnautica’s gameplay is one that throws you into the scary world of planet 4546B without much explanation or direction, letting you do what you want. The first few minutes are easy enough, but most players get stuck trying to find Subnautica Cave Sulfur.
The chaos that ensues is one that is all too familiar for every new player. Your oxygen tank is pretty low at the beginning of the game, and you aren’t all that fast. This can make finding the cave sulfur a tedious and potentially dangerous activity for multiple reasons, unlike bioreactor fuel. It’s very easy to drown, especially if you ignore or don’t notice your PDA warning you that you’ll run out soon.
There are also players that obtain cave sulfur early on in the game and don’t really look at it much later on. This means they’re missing out on utilizing this easy-to-find material to its maximum.
We’ve put together a guide to help you figure out everything there is to know about cave sulfur. From finding it and staying safe while doing so to how Subnautica cave sulfur can help you in the future, we have it all right here.
Where can you find Subnautica Cave Sulfur?
The two biomes where you can find cave sulfur are the Safe Shallows and Kelp Forest. As its name implies, you’ll mainly have to go cave diving to be able to find cave sulfur.
The Safe Shallows is the first area the player spawns in and the safest one, too. Well, unless you somehow manage to lead a Reaper there… Then they become the unsafe shallows. You can find most of the materials you need to get into the game here, and cave sulfur is a part of that.



To collect cave sulfur in the Safe Shallows, you’ll need to find the Sulfur Plant. You may or may not notice it at first, but once you’ve seen a picture it becomes a little easier to understand what you’re looking for. The plant is brown in color and not too impressive on its own. Its companion, the Crashfish, is a far more formidable foe. Once you’ve dealt with the Crashfish, you’ll find cave sulfur sitting inside the plant.



The Kelp Forest is another option for finding Subnautica cave sulfur, namely in all the caves you can find in this biome. The Kelp Forest is definitely not as safe as the Safe Shallows as there is some aggressive fauna to encounter. This biome is the home of Stalkers, which is a rather aggressive shark-like creature that attacks the player in proximity. Once you enter the caves, however, the only creatures you should look out for are the Crashfish and Mesmer.
How to fend off Crashfish when mining Cave Sulfur
All Sulfur Plants have Crashfish inside them, which makes your encounter with these aggressive little fish unavoidable. However, there are a few tips to make it easier for players to deal with them.



It’s possible to kill Crashfish before the Sulfur Plant opens. To do this, simply sneak up to the side of the Sulfur Plant and strike it with a knife. Note that this isn’t possible for all Sulfur Plants, as the plant needs to be on a convex surface to do so. Then, striking the plant with a knife should make the Crashfish explode inside. This way, it will die and not damage you or the plant itself, allowing you to collect the Subnautica cave sulfur in peace.
Other than that, there’s really no other way to deal with Crashfish. It is advisable to wear protective gear and upgrade your fins as soon as possible to swim away from it faster. You can also swim straight towards the Crashfish and try to get behind it as it goes in to attack you. Because it’s slow to turn, this makes it easy to evade. The player will have to do this immediately, otherwise, it’ll be too late to evade the explosion.
What do you need Cave Sulfur for in Subnautica?
Cave sulfur has three uses in crafting, one of which is detrimental to getting through the game.
This crafting recipe is the Repair Tool, which is why the player will need to find cave sulfur within the first hour of playing the game. It’s important to craft a repair tool to be able to fix the interior of Lifepod 5. This recipe also requires silicone rubber and titanium.



The second important recipe is the Laser Cutter. Players who need to clear through the Aurora to stop the radiation will find this tool incredibly useful in their quest. It can also open sealed doors in Wrecks you find throughout the game. Aside from Subnautica cave sulfur, the recipe also requires 2 diamonds, a battery, and titanium.
Finally, cave sulfur can be used to create 5 Flares in Subnautica. Flares are great for illuminating dark areas such as caves. This makes them great for finding your way around and farming resources. It’s also possible to distract Bonesharks and Crabsquids by throwing a flare, as they are attracted to light sources.