Can I alter the biome of an area?

Question

In part 3 of my adventures, I would like to find out if there is a way to change biomes.

In part 2, fredley said that it is possible to move terrain from one world to another, but the biomes wouldn't match.

Is there any way I can change the biome of a specific area to, say, Savanna?

Answer 1

When Minecraft 1.2 is released, using the new “Anvil” file format, biomes will be stored in the chunk data so that they can be redefined on a per-column (x,z) basis. You will need an editor which supports doing so, or a generic NBT editor, of course. (Source)

Answer 2

This answer is now obsolete, please see Kevin Reid's answer for current information.

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According to this, biomes are dependent on the level seed stored in the world. So, it means that, for every chunks, biomes are not saved in the chunk, but regenerated each time. You only chance a changing a biome would be to change the seed, but it would change every biome on the map, and new chunks won't match the old ones.

Answer 3

Since 1.2 introduced the Anvil Format, WorldEdit (either SP or via bukkit) provides the //setbiome command to change the biome directly in-game.

For bukkit, there is also BioMed, which I have not used - it seems to offer some features WorldEdit doesn't, like "Convert whole maps to the same biome!" and "Spawn nether mobs in a normal world!"

For out-game: the MCEdit FAQ states

Can I use MCEdit to edit the weather/biomes/temperature/snowfall?

Currently, you can't. The new Anvil format does store biome data in the region files now, however, so the ability to do so will be added in a future version. Otherwise you can change the random seed, but that has other side effects.

However, this post claims you can use this MCEdit plugin to already modify the biomes, though I have not yet tested it.

Answer 4

Yes, but you must use a plugin called WorldEdit. This will allow you to change the biome of a world chunk-by-chunk, using the //setbiome command.

The worlds you create will be compatible with vanilla Minecraft, so other people playing in your world will not need to have WorldEdit or any other mods installed for it to work.