How to Replace One Biome With Another Using Biome Replacer

Find and Open the Config File

After the mod has generated its config on first launch, look inside your config folder for biome-replacer.properties. Open it with any plain text editor. Each line you add is a single replacement rule, so you can stack as many as you need.

Write a Replacement Rule

Use the format old_biome > new_biome. For example, to turn every desert into a plains biome, you would write minecraft:desert > minecraft:plains. Use the full namespaced ID of each biome, which is the same ID you would see in the F3 debug screen or in a datapack's biome JSON. The left side is the biome being removed, the right side is the biome that takes its place. You can chain multiple rules on separate lines to remap several biomes at once.

Apply and Verify

Save the file and restart the server so the rules load. Newly generated chunks will use your replacements. Already-generated chunks keep their old biome data unless you regenerate them, so test in fresh terrain. If a rule does nothing, double-check the biome ID spelling and confirm the mod is loaded server-side, since the config is only read on startup.