In 1999 Emperor released "IX Equilibrium", Tveitan's third studio album with the group. Two years later, in 2001, Peccatum released their second studio album, "Amor Fati." In the same year, Emperor released their fourth and final studio album, "". 'Prometheus' was entirely composed by Tveitan and featured more complex orchestration than previous works; though significantly less synthesizers than before. It was at this time that Emperor mutually decided to dissolve, leaving Tveitan and his bandmates with more time to focus on their various side projects.