The Undergrounds are mainly composed of Dirt Wall and Dirt Ground, with small patches of sand, tuff and some ancient structures scattered around. There is only Copper in this biome and sometimes Crates can be found containing different items. Slimes spawn occasionally anywhere, the mini-biome that Glurch the Abominous Mass spawns in can be found at the edge of this biome in a random direction. Also known as the dirt biome.
Old "the Undergrounds" passage