The series takes place in the fictional land of Nosgoth—a gothic fantasy setting—and revolves around Kain's quest to defy his fate and restore balance to the world. ' introduced another antihero protagonist, Raziel; the adventures of both characters culminate in '. Themes of destiny, free will, morality, redemption and the hero's journey recur in the storyline, which was inspired by ancient literature, horror fiction, Shakespeare's plays and gnosticism. The "Legacy of Kain" games have enjoyed critical success, particularly receiving praise for high-quality voice acting, narrative, and visuals, and, as a whole, had sold over 3.5 million copies by 2007.