Wars in the south and north.

According to QQ Music query, the song "Proud Boy" was released in 2015. It was written by Zhao Chenlong and composed by Ting Yang. The original song was "Southern Expedition and Northern War". In October 2015, the work became the ending theme of the second season of the patriotic online animation "That Rabbit That Year".

"Proud Boy" is the ending theme of the second season of the patriotic online animation "That Year of the Rabbit". "That Year of the Rabbit" is an animated film produced by the Chinese animation production company Shanghai Yixialitian Culture Media. The film tells various stories about a group of rabbits and other creatures on the Blue Star.