Barren Biome

The Barren Biome is a cold, mostly empty biome found in some asteroids and world traits. It is defined less by special resources than by what it lacks: there are no critters, no plants, and usually no liquid water pools. Most versions are made of hard, frozen terrain, so exploration tends to be slow unless a Duplicant has the digging skill and access to better tools.

In its standard form, the biome is cold, typically ranging from -46.15 to -16.15 °C. A CO2 Lakes variant exists that is even colder, around -73.15 to -46.15 °C, and a Solid variant can reach -213.15 to -73.15 °C. In practice, the biome is often built from Granite, Ice, Polluted Ice, and Snow, with Oxygen and Carbon Dioxide trapped in some variants. Because the area is so cold, small amounts of Liquid Carbon Dioxide may form naturally.

Several special features can appear inside it. The CO2 Lakes variant can contain a sand deposit feature and a liquid carbon dioxide lake surrounded by Granite, Ice, Polluted Ice, and Snow. Other points of interest include an Anti Entropy Thermo-Nullifier, ruins, and up to two buried geysers. The Solid variant has no terrain features at all and is used in the Frozen Core world trait.

The biome is useful mainly as an early source of materials and an obstacle to overcome rather than a productive region on its own. A large amount of refined metal can spawn here, making it a convenient place to bootstrap Smart Batteries and other automation once a miner can reach it. Its lack of gas also makes it easier to pressurize with your own atmosphere than many other biomes, although the hard, frozen rock still makes excavation time-consuming.

A few practical points stand out:

• Melting Ice and Snow tiles directly yields twice as much water as mining them first and then melting the debris.
• Venting excess heat into the biome is usually a bad idea if wild Sleet Wheat is present, since warming the area will disrupt it.
• The absence of gas makes the biome easier to control once breached, but the frozen terrain slows access to the resources inside.

The Barren Biome is a non-feature biome and was not explicitly listed in the release notes. It also has several known variants, including two Forest Biome-based versions and one Regolith Biome-based version.