This page discusses how to generate custom blocks in your world using outside custom item plugins such as MMOItems and CustomItems (these two just for sake of example, there are likely other custom item plugins out there worth checking out). For information on configuring ore generation with Terra, see Ore Configuration.

This tutorial is for Bukkit only. On other platforms, simply use the namespaced ID of the block you want, the same way as you would any Minecraft block.

It's important to understand that custom item plugins do not actually add new blocks to Minecraft, but instead replace existing blocks. The blocks of choice are usually Brown and Red Mushroom Blocks due to their many block states. As of Minecraft 1.14, the way in which Mushroom Blocks are handled has changed from numeric IDs to directional facings. As a result, this guide will be covering Minecraft 1.14 (and above) versions only.

Knowing custom blocks are mushroom blocks, we will be using this to figure out how to have custom ore generate in your world with a unique texture (thanks to your custom item plugin, note that Terra by itself does not offer such a feature).

When you create a custom block (using a custom item plugin!) and place it on the ground, if you did everything correctly, you will see a custom block instead of a mushroom block. So, how do we get this block to generate in your world naturally?

After creating a custom block, place the block on the ground and press F3 to bring up Minecraft's debug screen. The information we need is the block state information on the right:

This information will only show if you're looking at the custom block.

The information highlighted is the most important, but directly above it is whether it's a red or brown mushroom block. In this example, it's a red_mushroom_block. You'll want to know this information, too. The combination of whether it's a red or brown mushroom block and the facings in which they are true or false will be unique to each type of custom block you have and will be key in determining what spawns where and how in your Ore Configuration.

Navigate to your ores folder and create a new .YML file. In my example, I want my custom block to generate with a similar size to diamonds, so I'll take the provided minerals/diamond.yml's setup as an example:

material: "minecraft:red_mushroom_block[down=false,south=false]"
size:
  min: 8
  max: 8
extends: MINERAL
id: "SAPPHIRE_ORE"

The big takeaway here is the material: field. As shown in our example, our block was a red_mushroom_block (and not a brown_mushroom_block), so we set that as the material. However, in order to grab the facings, we must review which facings were false. By default, all facings are true, so for every facing that is true, you don't need to include it anywhere. You only need to include what is shown as false.

In our case, both down and south were false, so we include that with square brackets right next to the material (with no space!). You use a comma with no space to separate each facing that is false. Feel free to copy and paste the above example and adjust the values as necessary for your own custom block.

the id field can be anything we wish. In this example, I opted for SAPPHIRE_ORE. This is what you'll use for Terra to generate it into your world.