Luna's Simple Dungeon

Luna's Dungeon is a Minecraft datapack that makes a new, custom dungeon generate in your world. This adds a fresh new way to explore underground while still keeping it overcomplicated or less-vanilla. It also serves as a difficult challenge as a lot of monsters spawn in these dark corridors.

Installing this is easy, just download it, make a new world, and move (or copy) the zip file into the datapacks folder, then create the world and it'll generate underground!