Some mods/modpacks have biomes that are super rare or special that they may want to hide from the compass to prevent cheesing/breaking balance. The best way to handle this would be to add a Biome Tag that modpack makers or mods can add their special biomes to in order to hide from the compass. If a player wishes to undo that, they can override the tag with a replace:true empty tag to show all biomes again.

The biome tag can be something along the lines of naturescompass:hidden_from_compass and be placed under data/naturescompass/tags/worldgen/biome/hidden_from_compass.json

This would be for 1.18.2 and newer Mc version as biome tags were introduced in 1.18.2.

The current way to hide biomes from the compass is through the biome blacklist in the config file. I think it may be confusing to have two systems that basically accomplish the same thing, however I can see how biome tags might be useful, as biomes could then be hidden at the mod level, by the mod developer, and not just at the modpack level. I'll think about this.

Hmm. Wondering if maybe adding a BiomeBlacklistDataSource config option that has three states of: “ConfigOnly”, “TagOnly”, “Both” and is defaulted to “Both”. (And the comment explains what values are allowed and what it does) That way it is a little more clear to users what the source of the blacklist is and can change it to just the config or tag if they wish. Thus not needing a datapack to disable the tags if they want to handle it through just the config regardless of other mod’s tags. Just throwing ideas out there.

I think it may be confusing to have two systems that basically accomplish the same thing, however I can see how biome tags might be useful, as biomes could then be hidden at the mod level, by the mod developer, and not just at the modpack level. I'll think about this.

@MattCzyr One method I have seen is using three layers:

1. Config blacklist - for global modpack-level blacklisting
2. Tag blacklist (e.g. #naturescompass:unsearchable_biomes) - for mod-level / datapack-level blacklisting
3. Config whitelist - overrides both the config blacklist and the tag blacklist, all biomes in the whitelist would be searchable

This would work with the current system by allowing all biomes to be shown/hidden in the config, while also allowing mods/datapacks to hide biomes by default using the tag system.

Can’t the config biome blacklist also take in tags? Like doing #naturescompass:hidden_from_compass as an entry in the blacklist will pull the biomes from the tag to use in the blacklist. So now the blacklist supports both explicit entries and tag entries

This is now important in 1.20.5 and newer as Fabric and Neoforge now has a c: hidden_from_locator_selection biome tag that will hold biomes that other mods should not be able to locate

https://github.com/neoforged/NeoForge/blob/9b3bb00fa77c13ebbebf101a10d849c749523e8e/src/main/java/net/neoforged/neoforge/common/Tags.java#L1079