Legend has it that this was the nickname of Liu Yu, Emperor Wu of the Southern Song Dynasty. Before he became emperor, he led his troops to win a battle. When he was chasing and annihilating the remaining enemy soldiers to a mountainside, he encountered a big snake blocking his way. He shot the big snake with an arrow, and went there to take a look the next day. He heard the sound of people smashing something, and found several children making medicine. When he inquired, he found out that their king was injured by an arrow and was making medicine for it. After applying the medicine, Liu Yu drove away the children and took back their medicine, which was a good medicine for treating golden sores. People didn't know the name of this medicine and called it "Liu Jinnu".