Alissa White-Gluz is a Canadian singer, best known as the lead vocalist of the Swedish melodic death metal band Arch Enemy, and former lead vocalist and founding member of the Canadian metalcore band the Agonist. Her vocal style includes both growling and clean vocals (singing). Although primarily associated with melodic death metal and metalcore, she has appeared as a guest vocalist for power metal, symphonic metal and deathcore bands, notably Kamelot, Delain, Carnifex and Powerwolf, and has performed live with Nightwish and Tarja Turunen.

Powerwolf is a German power metal band founded in 2003 in Saarbrücken by members of Red Aim. The band consists of vocalist Karsten Brill as "Attila Dorn", lead guitarist Benjamin Buss as "Matthew Greywolf", bassist/rhythm guitarist David Vogt as "Charles Greywolf", keyboardist Christian Jost as "Falk Maria Schlegel" and drummer Roel van Helden. The group uses religious themes and images, contrary to traditional power metal music, as well as corpse paint, gothic-tinged compositions and songs about werewolf and vampire legends.