Navigating the Toxic Caves and Crafting Protective Gear
The Toxic Caves biome presents unique challenges and resources. To safely explore this hazardous environment and utilize its materials, you will need to craft specific protective items and understand the biome's features.
Toxic Caves Hazards
The Toxic Caves biome is a subterranean destination with its own distinct appearance, including ambient particles, fog, and light. A significant hazard within this biome is the Acid Pit. These pits generate within the Toxic Caves, with one attempt made per 6x6 chunk region, ensuring they are at least 3 chunks apart from each other.
Crafting Protective Gear
To protect yourself in the Toxic Caves, you can craft a 
Hazmat Skull Block and 
Polymer Plates.
Hazmat Skull Block
The Hazmat Skull Block can be crafted using:
- 8
Hazmat Block - 1
Skeleton Skull
Alternatively, it can be crafted with:
- 8 Hazmat Block
- 1 Wither Skeleton Skull
Polymer Plate
To create a Polymer Plate, combine the following ingredients in a shapeless crafting recipe:
Toxic Paste
Bottle of Radon
Sulfur Dust
Iron Ingot
Toxic Caves Resources
The Toxic Caves offer valuable resources, primarily 
Uranium and 
Uranium Shards.
Uranium
Uranium can be obtained through several methods:
- Blasting: Process
Radrock Uranium Ore in a blast furnace. - Smelting: Smelt Radrock Uranium Ore in a furnace.
- Shapeless Crafting: Break down a
Block of Uranium. - Shaped Crafting: Combine 9 Uranium Shards.
Uranium Shard
Uranium Shards are also available:
- Blasting: Process
Unrefined Waste in a blast furnace. - Smelting: Smelt Unrefined Waste in a furnace.
- Shapeless Crafting: Break down Uranium.
Crafting a Nuclear Furnace Component
Uranium is a key ingredient for crafting a 
Nuclear Furnace Component. This component is made using a shaped crafting recipe:
- 4 Uranium
- 4
Charred Remnant - 1
Blast Furnace
Processing what you mine
Two ores here go straight through a blast furnace:
- Radrock Uranium Ore blasts into Uranium
Guanostone Redstone Ore blasts into 
Redstone Dust
The redstone entry is easy to overlook and is the more immediately useful of the two — guanostone is common in these caves, which makes them a genuine redstone source rather than only a uranium one.
Eating in the caves
The toxic caves have their own food chain, and it cooks in any of the three vanilla heat sources — campfire, smoker or furnace all take the same inputs. 
Radgill is the local fish and cooks like any other, so a campfire at your entry point turns the caves into a self-supplying trip rather than one limited by the food you carried in.
The structures down here
Acid Pit generates at spacing 6, which puts it among the more common of the mod's fourteen structures — common enough that a thorough sweep of a toxic cave system will usually turn one up rather than needing a dedicated search.
Order of operations
Gear first, then ore. The protective equipment described above is what makes the rest of the cave survivable long enough to mine it, and uranium in particular is not worth attempting on a first visit — come back for it once the hazmat set is complete.
Covers the mod’s in-game guide topics: Uranium Uranium Shard Hazmat Skull Block Polymer Plate Nuclear Furnace Component Acid Pit