Kjell Åge Hartveit Karlsen is best known for being the loud, wild and untamed lead guitar-player and co-songwriter in the Doomsday Rock N Roll band Chrome Division , along with his partner in crime, Shagrath from Dimmu Borgir. Karlsen has a growing catalogue with band releases and several guest appearances, latest is co-writing and performing Faith Bloody Faith with Jorn for the Norwegian final of ESC 2021. He also has his own solo project called World Of Damage, and the debut album «Invoke Determination», guests some of the greatest names within the modern rock and metal scene, including Shagrath (Dimmu Borgir /Chrome Division), Roy Khan (Kamelot/Conception), Bjorn "Speed" Strid (Soilwork/The Night Flight Orchestra), Maurice Adams (Breed, Enigma Experience), and Chris Clancy (Wearing Scars) to name a few. 
 Karlsen has always had a very melodic side of him, and he is heavily influenced by artists like Al Di Meola, Paco de Lucía, Kiko Loureiro, and a wide variety of classical music.