Nachtmystium was an American psychedelic black metal band formed by Blake Judd, formerly known as Azentrius, and Pat McCormick. The band's name is derived from the German word Nacht meaning "night", and the made-up term mystium which resembles the Latin adjective mysticum. Judd and McCormick combined the words to create the band's name, which they state means "Encompassing Darkness". Nachtmystium released multiple critically praised albums between 2005 and 2012, including Instinct: Decay (2005), Assassins: Black Meddle, Part I (2008), and Silencing Machine (2012). Controversy marred the band's success in 2013, when Judd was arrested for theft charges and publicly admitted he had a severe drug problem. Over their 13-year run, Nachtmystium released seven full-length studio albums and headlined multiple concert tours.