"Farming lava is one way we keep Mata Nui green and healthy. When lava cools, it makes the best soil. With our farming, Le-Koro grows green, Ga-Koro's waters bountiful, and Onu-Koro's mines rich. But like the twobrothers, the fire of the Mangai is both a force of creation, and a force of destruction. To farm lava takes great Courage."
Lava Farming was a type of work usually performed by Ta-Matoran on Mata Nui. These Matoran farmed lava by draining it out of the Mangai Volcano and using it for different applications, such as hardening it to create tools, or making soil from slightly cooled lava.
When the Piraka forced the Voya NuiMatoran of all types to drain the volcano's lava, some witty Matoran called it "Lava Farming".