He is the third Fighting Game character to lose, after Riptor and Lord Raiden, and with the next four being Dan Hibiki, Johnny Cage, Sindel, and Goro.Nightmare is the fifth Fighting Game character to fight against a Non-Fighting Game character, after Zangief, Riptor, Lord Raiden, and Blanka, and with the next four being Dan Hibiki, Johnny Cage, Sindel, and Goro.He is the third Video Game character to lose, after Shadow the Hedgehog and Ryu Hayabusa, and with the next three being Dan Hibiki, Mega Man, and Red.Nightmare is the fourth Video Game character to fight against an Anime/Manga character, after Shadow the Hedgehog, Ryu Hayabusa, and Kirby, and with the next four being Dan Hibiki, Mega Man, Red, and Lucario.He is the second Soulcalibur character to appear, after Ivy Valentine.He is the second Bandai Namco character to lose, after Ivy Valentine, and with the next four being Renamon, Jin Kazama, Amuro Ray, and RX-78-2 Gundam.Nightmare is the fifth Bandai Namco Character to appear, after Dig Dug, Ivy Valentine, Zechs Merquise, and Gundam Epyon, and with the next seven being Tai Kamiya, Agumon, Renamon, Jin Kazama, Amuro Ray, RX-78-2 Gundam, and Heihachi Mishima.Nightmare's broken Soul Edge can be seen in the background during Juri VS Mileena. Ripped a hole between dimensions with Soul Edge.As Dumas, thrust Europe into a continent-wide war.Obliterated Ostrheinsburg Castle in a single blow.Remembers the fighting style of all previous Nightmares.Known hosts: Arcturus, Zasalamel, Cervantes, Siegfried, Pyrrha.The personification of Soul Edge and Inferno.Malfestation Curse: Turns victims into mindless slaves of bloodlust.Can take various forms based on the wielder.Nightmare is intent on plunging the world into darkness and, with the power of Soul Edge, may achieve it if not for its eternal rival, Soul Calibur. But it wasn't the end of Nightmare, as Inferno re-animated Siegfried's discarded armor and used it to hunt down Siegfried and continue its reign of terror.
Nightmare would terrorize Europe for years, until Siegfried was able to separate himself from the evil sword.
Nightmare's spirit, Inferno, promised Siegfried that if he gathered enough souls, he would resurrect his dead father. The Azure Knight first gained physical form by possessing the body of a noble knight named Siegfried Schtauffen and would constantly battle him for total control. Nightmare is living embodiment of the legendary and cursed sword, Soul Edge.