Soul Edge
Even though Nightmare originally debuted in "Soulcalibur", its predecessor, "Soul Edge", featured a prototype of his character. In the home version, an extra character named "Siegfried!" (an alternate version of normal Siegfried taken from his no-input ending, where he was consumed by the cursed sword Soul Edge) was added as an unlockable character. This early version has crimson armor and a more flesh-like design, almost as if he were part of Soul Edge itself; he has no story nor ending, and only used Siegfried's Soul Edge without effects. Nightmare has appeared as a playable character in all the main sequels to "Soulcalibur", visually different for each game.