Red Nova, known as Scar-Red Nova (sometimes translated as Scarlet Nova) in the Japanese version, is the Crimson Devil and the strongest of the Earthbound Immortals. It is known to be a mercilessly brutal demon, to the extent that even the Dark Signers did not dare attempt to harness its power.
The Crimson Devil has a fire demon servant, the Familiar of Red Nova, who planned to offer the body of Jack Atlas as a vessel, to awaken the Crimson Devil from its 10,000-year slumber. It is said to be associated with the serpent Nazca Line.
Towards the end of the ritual Duel between the Demon's servant and Jack Atlas, Red Nova was summoned by his servant to take Jack. However, the Crimson Dragon appeared, helping Jack acquire the necessary power through Blazing Soul to capture Red Nova and seal it into "Red Dragon Archfiend", giving it the ability to evolve into "Red Nova Dragon".
- At the time of the release of the material involving Red Nova, the Serpent Nazca Line was fictional, but in 2014, a sandstorm uncovered a real Snake Line.
- At the time of its introduction, Red Nova was the second largest monster seen in the anime; behind the Great Leviathan, though both have since been surpassed.
- Due to complications involved with dubbing the episodes, the story of Red Nova was skipped; as a result, in the English Dub, Jack summoning Red Nova Dragon (its tamed form) in the finals of the WRGP was a surprise to his teammates.
- Janet Fang (July 8, 2014). "Sandstorm Uncovers New Nazca Lines | IFLScience". http://www.iflscience.com/environment/sandstorm-uncovers-new-nazca-lines/. Retrieved September 14, 2016.