Phazon

The mysterious substance known as Phazon is a poisonous soliquid that is used by the Zebesian Space Pirates to mutate things and turn them into dangerously powerful forms. The evil being known only as the Metroid Prime endlessly searches for more phazon. Space Pirates mine this substance on various planets like Tallon IV and Dark Aether, and usually die due to exposure to it, hinting at their unintelligent nature. Metroids mutate on contact with it.