Biome Modifier for Fabric
Biome Modifier for Fabric is a library that lets datapacks add, remove and replace placed features and entity spawns in biomes through JSON files.
What it does
Datapack developers write biome modifiers as .json files in the biome modifiers directory of a datapack. Each file sets a type, a target biome selection and, optionally, a priority, so the mod can apply several datapacks compatibly. Modifiers with a smaller priority value apply earlier, and the default is 1000. The mod provides nine modifier types, covering placed features, entity spawns and spawn costs.
The mod is meant for datapack authors who want to change world generation without overwriting biome files. A replace type lets a datapack take over a modifier from another datapack. Entity spawn modifiers can add or remove spawns and their spawn costs, including spawn potential and spawn density. The mod is published for Fabric only, across 11 release versions 1.20 – 1.21.3, and runs on the server side alone. Its code is open source under the MIT License.
Key features
Placed feature modifiers
Modifiers can add placed features to target biomes, or remove features named in a features field.
Entity spawn modifiers
Spawn entries can be added to target biomes, or removed by entity type.
Spawn cost modifiers
Modifiers add or remove spawn costs, covering spawn potential and spawn density.
Replace modifier type
A replace type allows a datapack to override modifiers that other datapacks define.
Gallery
Compatibility
Latest build for each game version and loader.
1.21.x4 of 4 versions with builds
1.20.x7 of 7 versions with builds
Only full game releases are shown. This mod publishes no snapshot builds.
How it compares
Dynamic Registries Modifier is open source under the CC0 1.0 Universal license, works on Fabric for 1.21.1 – 1.21.8 and can run on the client or the server. Loot Modifier is open source under the MIT License, Fabric only, for 1.21.5 – 1.21.8, and server-side only, but it changes loot tables rather than biomes. Biome2 is not open source under the Apache License 2.0, runs on Forge and NeoForge for 1.20.1 – 1.21.4, and is server-side only.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Biome Modifier for Fabric | Fabric | 1.20 – 1.21.3 | Server-side only | 2026-02-03 |
| Dynamic Registries Modifier | Fabric | 1.21.1 – 1.21.8 | Client or server, optional | 2025-08-23 |
| Loot Modifier | Fabric | 1.21.5 – 1.21.8 | Server-side only | 2025-09-21 |
| Biome2 | Forge and NeoForge | 1.20.1 – 1.21.4 | Server-side only | 2025-04-29 |
Questions
Does Biome Modifier for Fabric need to be installed on clients?
Which loaders does Biome Modifier for Fabric support?
What does the priority field control?
In the catalog
Biome Modifier for Fabric is one of 3,514 Library mods on ModsFinder, and one of 2,348 Library mods for Fabric. 13,252 mods support Minecraft 1.21.3.
More from Viola-Siemens
Similar mods
What the author says
This is a library mod that allows users utilize datapacks to modify biomes easily and compatibly. Datapack developers should put all biome modifiers (with format *.json) on data/ /biome_modifiers/ directory. With this mod, all biome modifiers will be applied on each biome.
Official listing
- Modrinth page
- modrinth.com/mod/biome-modifier-for-fabric
- Owner
- Viola-Siemens
- Published
- 2024-07-06
- Updated on Modrinth
- 2026-02-03
- Facts verified
- 2026-10-15