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. Initially regarded as impossible to do, the technique was invented by Toph Beifong to escape from a metal cage in which she was captured and transported by Xin Fu and Master Yu. Metalbenders can also bend liquid metals, such as mercury, though utilize more fluid movements to do so, akin to waterbending. It is also possible to bend liquid metal inside someone's body.