 Now more than half of Nox Arcana's CDs contain some sort of hidden puzzle, which is left to the listener to discover.Nox Arcana's music is often used to provide atmosphere for films, public events, role-playing games and during Halloween at theme parks, several of which have based haunted attractions on Nox Arcana's original theme albums, "Transylvania" and "Blackthorn Asylum".Nox Arcana's music is melodic and moody, focusing on a dominant melody line.