The Legions of Terror are well known for their fondness for writing songs about basically everything they do. This tendency is at its strongest with major or amusing victories. It is, unsurprisingly, popular with the Legions and unpopular with Callowans.
Only one verse of the song to be mentioned is the first. It was sung by a minstrel named Ellerna at the Rat's Nest, but Catherine stopped paying attention after the first verse and the rest of the lyrics have not been revealed.
“Boot goes up and boot goes down:
There goes their callow crown
And no matter how high the walls
We’re all gonna make them fall-”