Changing biomes on an existing map

Sometimes you need to turn a desert at spawn into plains, or set up a snow zone for an event.

Using WorldEdit

//pos1
//pos2
//setbiome plains
//expand vert

Changes the biome in the selected region. Players' grass and water colors will update after they relog or the chunks reload.

What changes

• Grass, foliage, and water color.
• Weather: snow instead of rain.
• Mob spawning based on the biome.
• Plant growth.

What does NOT change

Terrain and blocks. The desert stays sandy until you replace the blocks — WorldEdit: brushes.

Refreshing for players

The client caches chunk data. For players to see the changes, they need to relog or walk away and come back. This is normal for large areas: don't assume the command didn't work.

Limitations

• The operation is heavy on large areas: do it during maintenance.
• A backup is required: it's the only way to roll back a biome change.
• On modpacks, modded biomes require the full name with the mod prefix.