Demon Knight was born during the Nightmare Wars with Meta Knight, there house was burned down by two Nightmare demons that could spit fire, Meta Knight was seperated from Hyi(Demon Knight's real name). He almost died from huge Nightmare Demons with Shotzo's on there backs witch where stomping soo close to him he could of been killed. He fell asleep for four years and found a dark sword called Antilixia, the reminants of some Demon Beasts and started fighting as a spy for the Nightmare Demons,