Metalbending is a specialized sub-skill of earthbending that
allows an earthbender to ferrokinetically bend processed metal in a similar
fashion to bending regular earth. The technique was invented by Toph Beifong
after Xin Fu and Master Yu captured and transported her in a metal cage, from
which she escaped through the use of the skill. Metalbenders can also bend
liquid metals, such as mercury, though utilize more fluid movements to do so.
It is also possible to bend liquid metal inside someone's body.