WorldJava

/fillbiome

Overwrites the biome of every block-column section in a 3D region, changing biome-driven features like grass/water color, mob spawns, ambient sound, and weather. Added in 1.19.4. Does not regenerate terrain — only the biome assignment.

What is /fillbiome used for?

What /fillbiome is for

Overwrites the biome across a 3D region, changing biome-driven traits like grass and water color, mob spawns, ambient sound, and weather.

When to use /fillbiome

Fix a biome that doesn't match your build, create a custom-themed area, or stop unwanted mob spawns by swapping the underlying biome.

What it doesn't do

It only changes the biome assignment — not the terrain or blocks. Use the 'replace' filter to convert only one existing biome within the box.

Syntax

Parameters

from / to
coords
Opposite corners of the region.
biome
biome ID
Biome to set, e.g. minecraft:desert.
filteroptional
biome ID
Only replace this existing biome.

Examples

  • Turn the area around you into plains.

  • Convert only plains within the box to desert.

Permission level

/fillbiome requires Cheats (op level 2). In single-player you need the world's "Allow Cheats" toggle on. On a multiplayer server you need to be opped — see /op.