How to Define Biome and Environment Temperature with Thermoo Datapacks

Thermoo's Environment API lets you control how hot or cold a location is using datapacks, independent of any single mod's hardcoded values. This is the main way to customize temperature behavior without touching Java code.

Where the files go

Create a datapack in your world's datapacks folder with a data directory and a pack.mcmeta. Thermoo reads environment definitions from its own namespace inside that pack. The exact folder path and file format are documented in the mod's datapack reference — follow that schema precisely, since malformed entries are silently ignored.

What you can control

An environment entry describes a temperature value for a context: a biome, a dimension, a time of day, or a combination. You can layer multiple sources so that, for example, a biome sets a base temperature and a modifier adjusts it at night or during rain. Thermoo resolves these into a single effective temperature for the entity standing there.

Testing your pack

After adding files, run /reload and use the Thermoo commands to read the temperature of a player standing in the biome you edited. If the value doesn't change, double-check the namespace, the JSON syntax, and whether another datapack is overriding the same biome.