General Mung was the ruthless overseer of the factory built on the shores of the Jang Hui River. A firebending master, he was a cold man who believed that military needs always outweighed those of civilians. He held great contempt for the villagers of Jang Hui and often ordered his soldiers to steal their food and medicine, referring to it as a "patriotic donation". The general took great pride in being part of the Fire Nation's war effort and hoped to serve on the front lines in the Earth Kingdom.
General Mung operated the factory which was polluting the water of the Jang Hui River, thus condemning the river village of Jang Hui to poverty. When Katara and AvatarAang destroyed the factory, he blamed the villagers, accusing them of stealing medicine and food supplies, although these crimes were actually committed by Katara when she masqueraded as the Painted Lady in an effort to help the villagers. Angered by the destruction of the factory, he and his soldiers began to destroy the village. However, before they could do any real damage, they were confronted by Katara in her Painted Lady disguise. She, with bending help from Aang, who was hiding under the docks, along with sound effects provided by Toph, Sokka, and Appa, was able to frighten and disperse Mung's forces. Mung, on the other hand, prepared to fight her, but a well aimed airbending blast from Aang threw him into the polluted water, where he was picked up by one of his soldiers on a jet ski. After Katara's powerful display, General Mung and his men left the Jang Hui area, warned by Katara never to return.
General Mung had a very large scar which extended from one side of his face to the other and went directly through the bridge of his nose. This scar showed that the Fire Nation used metal staples to help their soldiers heal.