Green Day has recorded a version of "21 Guns" with the cast of American Idiot. The recording was produced by Billie Joe Armstrong and was released on December 3rd to Spinner.com and also released for digital download on December 22nd.[7] Video was released Feb 1. [8]

Green Day released two versions of the song with the cast of American Idiot. One version had Billie Joe Armstrong as lead vocals for a brief portion of the song. The other version features John Gallagher Jr.