1.20.1

KubeJS worldgen on 1.20.1 is not that good. (Doesn't work)

Instead we have to use a datapack. This guide is only supposed to be a first point of reference if you want to change world generation using KubeJS.

Make sure to put this in: kubejs/data/mod_name/worldgen/configured_feature/identifier.json

This file needs to contain:

{
    "type": "minecraft:no_op",
    "config": {}
},

#All Ores

If we wanted to remove all minecraft ores, we would create ore.json in kubejs/data/minecraft/worldgen/configured_feature/ and insert the above code snippet.

The ore identifier removes all minecraft ores.

#Specific Ores

If we wanted to remove a specific ore it is a similar process.

You can find ores' identifiers here.

To remove iron we create a file at this path kubejs/data/minecraft/worldgen/configured_feature/ called ore_iron.json

This JSON file contains the code shown above.

#Custom:

I recommend you check out Misode's Configured Feature Generator (use the preset button on the right to get an idea of some vanilla worldgen) to generate the necessary files.

In order to change a vanilla worldgen feature name the file identifier-of-feature.json

Using a preset you could probably even add your own custom geode.