Many different materials can be found in Subnautica: below zero, each material has its own unique purpose. In most cases, most of the things that players encounter will be used for production in Fabricator or Habitat Builder, but this is not the main function of Root Pustules.
If these things that sound annoying are of no use in any form of crafting recipe, then a question arises as to why the player needs them in the first place. As it happens, this material is very useful and can power the player’s base.
In Subnautica: Below zero, it is not enough for players to eventually return to the same thrown capsule every time to make items. When this happens, the next logical step is to build the bases elsewhere, and eventually the player may even have multiple bases running at the same time. The problem is that all of these bases need fuel to stay lit.
To find the root pustules, players need to travel to the Arctic kelp cave biome, because this is the only place where they naturally spawn. As the name suggests, they show a strange yellow growth under the kelp roots in the area. Players don’t need any tools to collect them, so the hardest part of getting these root pustules is to find them. Seatruck will come in handy here because it allows players to travel faster and deeper than other methods.
Although players can use many different options to power their foundation, one of the most convenient methods is a bioreactor. When used in a bioreactor, root pustules can provide an impressive 700 energy, which is the highest energy provided by any item in the game. Therefore, it is easy to understand why they are so valued, because keeping them is a good way to ensure that there is never any power shortage. Later, the choice of nuclear and solar energy is often better, but in some areas this type of electricity will not work properly.
This is a smaller spoiler, but two root pustules were also used when creating the architect component, and players need to use it in the rest of the story. No matter what the player needs, they should have an easy time in the future to find the root pustule.