In August 2008, King Diamond was asked by Metallica drummer Lars Ulrich if Mercyful Fate would be willing to participate in Activision's Guitar Hero: Metallica video game.
U kolovozu 2008., Metallicin bubnjar Lars Ulrich upitao je Kinga Diamonda bi li Mercyful Fate želio sudjelovati u Activisionovoj igrici Guitar Hero: Metallica.