Crystal Castles is a Toronto-based band, consisting of multi-instrumentalist Ethan Kath (of Jakarta and formerly Kill Cheerleader) and vocalist Alice Glass (of Fetus Fatale). Crystal Castles are known not only for their own efforts as a band, but also for commissioned remixes for number of groups, including "Hunting for Witches" by Bloc Party, and "Atlantis to Interzone" by friends, Klaxons.   Wikipedia