Demons exist in levels or orders. The highest order of demons were those that exist at the cosmic level. These were the fallen gods and cosmic beings. The second order were the Lords of the individual Hells and their underlings. The third order were the class that exists in other dimensions that intersect with our native dimension.
In Marvel, Demons have been a staple of the magical world since the very beginning and they have run through each of these orders repeatedly. There are a number of extremely powerful demons that spend their time on Earth and toy with the lives of mortals.
Satana Hellstrom is a succubus who seduces her victims and kills them with a kiss, leaving them a desiccated husk. Their soul leaves the body in the shape of a butterfly that Satana feeds on. This powers her demonic powers.
Satana rules her own Hell. People were choosing which Hell to serve their damnation in and everyone wanted a “Hip Hell” with movie and rock stars, disgraced politicians and reality stars. Satana was desperate to make her Hell the “It” place to be. To that end, she wanted to have Doctor Strange as her marque star and she poisoned him but Strange got away through astral projection. Satana was forced to use her second choice: Jim Morrison.
Belasco is a 13th Century Alchemist and sorcerer spoken of in the writings of Dante. Belasco made a pact with the Elder Gods to create a portal into this dimension in exchange for immense power and immortality. This portal required an amulet with a pentagram of five Bloodstones to be created. In modern times, Belasco has battled Shanna the She-Devil, Ka-Zar, Witchfire and the Punisher in pursuit of this goal.
Belasco’s most implacable enemies in modern times have been the X-Men. Belasco trapped Illyana Rasputin in Limbo, stealing a piece of her soul to make a Bloodstone and awakening her Darkchylde. He attempted to corrupt Cable with the demon lord D’Spayre and to again claim the Soulsword, but was thwarted by Amanda Sefton.
8 The Adversary
The Adversary is an immensely powerful mystic entity that is known to the Cherokee People of North America as a trickster. X-Men associate Forge had been trained to battle him but turned away to go out into the world. The Adversary convinced Storm to confront Forge and stop him from destroying the world. Storm found that Forge was trying to close the portal just after she stabbed him. Storm and Forge were cast through the portal into an alternate dimension.
Storm and Forge return to Earth to find the X-Men battling time-displaced threats throughout Forge’s skyscraper home to thwart the Adversary’s plans and free the Goddess Roma. The X-Men sacrificed themselves so Forge can cast the spell that will lock the Adversary away for “an age”.
7 Damion Hellstrom/Son of Satan
Damion Hellstrom is the son of “Satan” and a human woman. Learning his origins, his father invited Damion to join him in Hell. Daimon went but instead battled Satan, taking his Trident and demon drawn chariot back to Earth. Daimon made it his mission on Earth to battle his father’s plans as the Son of Satan.
Daimon joined the Defenders and fell in love with Patsy Walker. Daimon lost his Darksoul and grew weak. Patsy summoned Satan to return it to him, causing her to go insane. Daimon became a Lord of Hell after slaying his father but, after a plot by Dormammu, he lost his claim to Mephisto. Later, Daimon would help Doctor Strange find the new Sorcerer Supreme, and he was killed by a possessed Victoria Hand.
The Town of Christ’s Crown, New York became so saturated with evil from the centuries of murders, the demon Mephisto was able to create a “son” with the accumulated negative energy. Blackheart’s primary tutelage from his father had been in the nature of evil. Thus educated, Blackheart has attempted to corrupt many heroes.
Blackheart briefly killed the Falcon by ripping his soul from his body and sending it to Hell but he was saved by Brother Voodoo. Mephisto had offered Miles Morales and Amadeus Cho the opportunity to revive the killed in action Ms. Marvel and Viv Vision for the life of a random innocent. Taking it further, Blackheart possessed members of the Champions and had them attack each other. His plan backfired and the team grew stronger.
Nightmare is one of the Fear Lords and began as a conceptual being but sacrificed a great deal of his power to take a physical form. He exists in his own Nightmare realm and can access humanoids through their dreams. Nightmare has taken particular joy in tormenting the Hulk with nightmares and hallucinations.
Nightmare has made several attempts to trap Doctor Strange in his realm or to kill him. He attempted to gain control of the Soulsword from Nightcrawler and Amanda Sefton. Nightmare attacked highly patriotic people through the idea of the “American Dream.” SHIELD Agent Sharon Carter and Captain America broke Nightmare’s influence over them.
4 Ghost Rider
There has been a Ghost Rider since the early days of man. The “shape” of the Rider is determined by the customs, beliefs, and era the Rider is created in. For example, the earliest Rider was a boy riding a flaming woolly mammoth in the year 1 Million B.C.
The best known Ghost Rider of the modern era has been Johnny Blaze. The one-time motor-cycle stunt rider made a deal with Mephisto to save his mentor’s life from cancer only to have the man die in a crash. Johnny was bound to the demon Zarathos. Johnny went on to usurp the mantle of the King of Hell from Mephisto with the help of the Spirits of Vengeance throughout time.
Lucifer is the angel that led the failed rebellion against Heaven and was cast down to Hell. Lucifer’s argument was that God loved his human creations more. Lucifer took the names “the Devil” and “Satan”. Both names have been used by many demons over the millennia. Lucifer rose to rule over most of Hell.
Unlike many Helllords, Lucifer cannot leave Hell under his own power. In recent times, he bound himself to the soul of Johnny Blaze and “rode” it back to Earth, dividing his spirit into 666 corpses. Realizing his plan, Ghost Rider destroyed his final host before Lucifer was able to access his infinite powers. The Rider was able to defeat Lucifer and send him back to Hell.
Mephisto is a centuries-old demon from a pocket dimension he calls “Hell”. While he is not the “Satan” from the Christian or Jewish religions, he allows people to believe he is for his own purposes. Mephisto feeds off of the evil and suffering of humanity and he wants to enslave as many souls as possible to fill his realm.
Mephisto has influenced the heroic world from the very beginning. He bound the first Spirit of Vengeance to a boy in 1,000,000 B.C. Mephisto has made repeated unsuccessful attempts to corrupt the noble soul of the Silver Surfer. Peter and Mary-Jane Watson Parker gave up their marriage and happiness for the life of Peter’s Aunt May and to erase the world’s knowledge of Spider-Man’s identity.
1 The One Below All
The One Below All would require a human host for even the smallest portion of it to manifest itself on this plane. It is beyond all classification of strength and ability. The One Below All is the source of Gamma energy and can possess gamma mutates.
It was present when Bruce Banner’s Gamma Bomb went off and unleashed the Hulk and the One has tried many times to use the Hulk and his allies to cross over but was defeated each time. In the far future, he managed to kill the Hulk, possess his body, calling himself the Worldbreaker and cross over. This being killed everyone in the universe, including the cosmically powerful Franklin Richards and Galactus.