[TUTORIAL] How to create underground stone layers

This was something I was struggling with for hours trying to figure out, as no one seemed to have an answer that either didn't involve code or didn't work fully. But it turns out the solution is embarrassingly simple, and here it is:

• First create the block you want to use as your deepslate substitute, then make a new Feature Element using the "Blackstone Blob" template.
  Set the blob to replace the naturally generated stone with your deepslate.
• Set the radius to 12, 12.
• Set the repeat to a high number (50 is a good low-end, but will leave patches of the natural stone here and there).
• And finally, define the height you want your layer to generate at. I recommend replacing the "X blocks from bottom/top of world" blocks with actual Y value blocks just for simplicity sake.

And there ya have it, a new stone layer will now generate in your world. You can repeat this process as much as you like to create a bunch more layers; in my case I have 3 layers in my mod, with a max world depth of -128 to better fit these layers into a custom dimension.