EDIT: this doesn’t work anymore, it was made in an old 1.17 snapshot. There’s other, much more well made versions of this on PMC made by other, talented people.

To enter the dimension, type this command:

/execute in unknowndepths:the_underground run tp (username) ~ ~ ~

This was made using misode’s dimension generator website, because I don’t know how to code anything: https://misode.github.io


take a look at it for yourself, and maybe you’ll learn how to make these too. I only made this so you don’t have to. I’m no professional at this.

List of biomes:
Plains (generic caves)
Dripstone Caves
Lush Caves
Desert (for fossils)
Badlands (dark oak mineshafts)
Basalt Deltas (this ain’t the overworld, something’s gonna be odd about it.)