Guangling Shi: refers to Qin Le Guangling San. A lost piece of music. Metaphor is a kind of lost knowledge and skill.

According to Jin Shu Ji Kang Biography, Ji Kang was good at playing Guangling San, but he didn't teach it to others. He was hurt by Si Mazhao. When he left, he asked for a piano. He said it again and said, "Guangling San will definitely fight today."