Underground Biomes Mod Wiki

The Underground Biomes mod (also known as Underground Biomes Constructs) completely overhauls the subterranean world of Minecraft. Instead of a single, monotonous layer of generic stone, the mod introduces 24 different types of real-world rocks categorized into three geological groups: Igneous, Metamorphic, and Sedimentary. These stones generate in massive "underground biomes" that are independent of the surface biomes, creating a diverse and realistic mining experience.

Beyond aesthetics, the mod adds functional depth by varying the hardness and blast resistance of different stone types. It also integrates seamlessly with other mods by providing "UBified" ore textures, ensuring that ores like Iron, Gold, and even modded metals match the specific stone they are embedded in. Players can use these new stones to craft a wide array of decorative blocks, including bricks, slabs, stairs, walls, and buttons.

The mod adds 24 stone types, each with its own physical properties. Igneous rocks are generally the hardest to mine, while Sedimentary rocks are the softest and often contain unique resources like fossils.

Igneous Rocks

Formed from solidified magma, these are the toughest stones in the mod.

Metamorphic Rocks

Rocks transformed by heat and pressure. They often appear in striking colors.

Sedimentary Rocks

Formed from compressed layers of sediment. These stones do not produce cobblestone when broken; they either drop themselves or specific items.

Every stone type comes with a full suite of decorative and functional variants.

• Cobblestone: Dropped by Igneous and Metamorphic stones when mined without Silk Touch. There are 16 types of cobblestone in total. Sedimentary stones do not have cobblestone variants.
• Bricks: Crafted from smooth stone. All 24 types have a brick variant.
• Slabs, Stairs, and Walls: Available for all stone, cobblestone, and brick types.
• Buttons and Pressure Plates: Available for all smooth stone and cobblestone types (bricks do not support buttons).
• Gravel and Sand: The mod adds 24 variants of gravel and sand to match the local geology.
• Monster Eggs: Silverfish can hide in any of the 24 stone types.
• Mossy Variants: Mossy cobblestone and mossy bricks are available for all applicable stone types.
• Overgrown Stone: Compatible with Biomes O' Plenty, adding grassy/overgrown versions of the stones for surface transitions.

Mining in Underground Biomes provides more than just building blocks. Several stones have unique drops:

• Lignite (Item): A low-quality coal dropped from Lignite stone. It can be used as fuel in a furnace, smelting 1 item per piece.
• Fossil Piece: A rare drop found when mining Limestone, Chalk, Siltstone, Lignite, or Dolomite. These can be crafted into Bone Meal or kept as decorative items.
• Flint: Frequently drops from Chert instead of the block itself.
• Clay: Occasionally drops from Shale.
• Rare Nuggets: Deep-level Igneous rocks have a very small chance to drop Gold nuggets or other modded metal nuggets.
• Gems/Dust: Deep-level Metamorphic rocks have a rare chance to drop Lapis Lazuli or Redstone dust.

Underground Biomes and Strata

The mod generates "Underground Biomes" which are large regions defined by a primary stone type. Within these biomes, the stone is organized into Strata—horizontal layers of different rocks. This means as you mine deeper, you will pass through distinct bands of color and material.

Ore Overlays (UBification)

To maintain immersion, the mod uses an overlay system for ores. When an ore generates within a UB stone, it adopts the texture of that stone.

• Vanilla Support: Coal, Iron, Gold, Redstone, Lapis, Diamond, and Emerald all have UB-textured variants.
• Mod Support: Many popular mods (like IndustrialCraft, Thaumcraft, and Thermal Expansion) are supported natively or through the UB API, allowing their ores to blend into the environment.

Most recipes follow the standard vanilla patterns, substituting the mod's stone types for vanilla stone.

Decorative Crafting

Resource Processing

Vanilla Stone Conversion

If you need standard Minecraft Stone for specific recipes, you can craft it using UB stones:

• 4x UB Stone (any type) -> 4x Vanilla Stone (2x2 square)

The mod is highly configurable via the undergroundbiomes.cfg file. Key options include:

• biomeSize: Controls the size of the underground biomes. A setting of 3 is default (~128 blocks); higher values like 5 or 6 create massive, realistic geological regions.
• UBifyOres: (Default: true) Enables or disables the ore overlay system.
• harmoniousStrata: (Default: false) When enabled, rearranges strata layers to ensure smoother color transitions (e.g., avoiding black-to-white jumps).
• replaceCobblestone: If true, world-generated cobblestone (like in dungeons) will be replaced with the local UB variant.
• dimensionSpecific: Allows you to enable or disable UB generation in specific dimensions (Overworld is included by default).