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This article is about The Thermal Spires Caves. You may be looking for the Hydrothermal Spire or the Thermal Spires.

The Thermal Spires Caves is a collection of cave systems spread throughout the Thermal Spires. The caves are accessible through entrances located around the perimeter of Delta Island.


The Thermal Spires Caves, like its parent biome, is littered with Hydrothermal Spire formations. The tunnels that make up the biome range from narrow to compact, and only support a handful of Oxygen Plants. The biome's fog is a drab and murky green, likely due to the intense, concentrated geothermal activity. Lava Geysers are found predominantly throughout the caves, making navigation without the aid of a Seatruck hazardous towards the player. The caves' ceilings are dotted with clusters of stalactites, and the only natural source of illumination comes from the Oxygen Plant and Lava Geysers. Diamond and Gold Ore Veins can be found close to the geysers as well.

The largest cave system serves as an alternative entrance to the Koppa Mining Site, leading the player to an open, mineral-rich area within the mines. Another, small cave system also leads the player into the site, close to the actual entrance.

One of the caves contains the Mineral Distillery.



  • The Thermal Spires Caves is the only biome to have no Fauna.