Immersion Pistons are used by Space Pirates in Magmoor Caverns in their geothermal processing operations. Pistons set in the walls of the Monitor Station are submerged at regular intervals into magma pools from which they leech energy to be used to run Space Pirate operations elsewhere. The use of Immersion Pistons in processing geothermal energy is the primary reason for the Space Pirate presence in the Magmoor region.
Scans in the Magmoor Caverns indicate that Space Pirates planned to recommend complete deactivation of the Central Dynamo in Phazon Mines immediately to Energy Command in favor of switching to geothermal power, but scans in the Central Dynamo reveal that, even producing energy in tandem, the geothermal and Dynamo power sources are not enough to sustain Space Pirate operations.
- "Immersion pistons are leaching power from the magma pools as planned. Geothermal power source is promising. Recommend Energy Command deactivate Central Dynamo and switch to geothermal power at once." —Scan Data (Metroid Prime)
- "Phazon Processing and security systems are taxing the Dynamo beyond safety tolerances. Though the conversion to geothermal power is easing the drain on our systems, it is not enough. Further power use at current levels could lead to system failure." —Scan Data (Metroid Prime)