Epica and The Black Halo are a two-part concept based on Goethe's Fauss. Memento Mori illustrates the ending, where Ariel (Roy Khan) defies evil in the very face of damnation. Because of this, Mephisto (Shagrath from Dimmu Borgir) is unable to claim Ariel's soul and is cast into Hell due to his divine bet with God (as explained in Epica). Ariel's soul is now split from his body and rises into Heaven to join his dead lover, Helena (Simone Simmons).