The Hellfire Club is an alliance of villains from many worlds, created by the evil witch Maleficent. They are not as tightly knit as some other villain groups, but work together to conquer the worlds. A few of them joined of their own will, while others were black-mailed into it by Maleficent. They are the arch-enemies of Team Paladin
The leader of the Hellfire Club. Her homeworld is the Enchanted Dominion. An evil and powerful witch of the darkness, most well-known for her attempt to take over the universe, but her plan was foiled by the keybearer, Sora. She was stabbed by Riku when he was possessed by Ansem, Seeker of Darkness, and eventually killed by Sora, Donald, and Goofy. She was resurrected a year later, and helped Sora and his friends when they were confronted with a heartless army in the World that Never Was. She survived, and took control of the Castle that Never Was. Some time later, Phoenix came to the World that Never Was in her search for Omega, and she met Maleficent, who tried to coax her into taking the darkness. Phoenix defeated her, and made a permanent enemy out of Maleficent.
Maleficent's right-hand man. His homeworld is the Kingdom of Disney. He was a servant in the castle, until he tried to kidnap Queen Minnie. Mickey--not yet King--defeated him, and won the heart of Minnie. Pete was imprisoned for a short while, and after certain events, King Mickey sealed him into another plane of Existence. He was freed by Maleficent, and proceeded to begin making a heartless army for her, even after her demise and resurrection. Since the taking of the Nobody base as their own, Pete has been seeking out potential members of the Hellfire Club.
An insane and sadistic scientist. His homeworld is Midgar. He is the biological father of Sephiroth, and the cause of all of the horrible things that have happened in the Compilation of Final Fantasy VII. He was thought to have been killed by Cloud and Co. but it was revealed that he had uploaded his mind into an equivalent of the Internet. He possessed a Tsviet, but was killed again, and it was thought that he had been eradicated. However, Maleficent collected the remnants of his mind and implanted them into a robotic body. However, he has a tendency to be a bit absent-minded because of missing bits of his mind. His current experiments deal much with Box Weapons, the Heartless, and Hollows.
A Reaper with a thing for mathematics. His homeworld is Shibuya. He became the Game Master of the Reaper's game, with the intent to wipe out the biggest threat, Neku Sakuraba. However, he lost to Neku and was thought to have been erased after absorbing Taboo Noise. It was later revealed that he had tried to kill the Composer, the creator of the Reaper's Game, but failed to do so. Maleficent retrieved his soul from the Realm of Darkness, with the promise that he would stay in her service. Unknowing to Team Paladin, he was the one who took away Neku's friends, sealing away their souls into Pins.
The Phantom Blot
The Blot for short, an evil conglomeration of paint and thinner. He originally came from the Timeless River. He spends his days trying to complete evil plans to take over the world, but most of the time fails thanks to Mickey and Co. He is skilled in hypnosis, disguise, escapism, and is knowledgeable on a variety of subjects. He has also recently acquired the ability to steal the colors from a person, turning them gray-scale, then use their abilities. However, he has a weakness to water.
A Yevon Maester and malicious Unsent. His homeworld is Spira. He tried to marry Yuna, so that he could become the Final Aeon and become Sin itself, a gargantuan whale-like creature, but was defeated by her friends. He managed to escape from the Farplane, and allied himself with Maleficent to get revenge. He is skilled in magic and summoning, and can also enter a fiend-like form to strengthen himself.
Former number VII of Organization XIII, the Luna Diviner, also referred to as the Berserker. When Axel kidnapped Kairi, Saix took Kairi from him to anger Sora. When Namine helped Kairi escape, Saix confronted them, and was about to kill them when Riku appeared. That moment of anger and pure unselfishness caused Riku to gain a keyblade, and he chased Saix away. Saix was killed by Sora while begging for his heart. Because of the strength that the moon gave him, Saix returned to the physical world, albeit in an unstable form. Only while the moon waxes does he remain stable, but at the new moon, he is nothing more than a ghost.
Phoenix King Ozai
Once a powerful firebender, reduced to a shell of his former self. His homeworld is Incarnate. He had his bending abilities taken away by Avatar Aang, and he was imprisoned. Pete came to the prison and freed Ozai. Maleficent restored his firebending abilities, however, Ozai soon discovered that he had to re-learn firebending. When Team Paladin first encountered him, he was at the approximate skill level that Zuko was at when Aang was freed from the iceberg. The chances of him ever returning to his original skill level are very, very low.
A mysterious man. He comes from Jump City. He is the arch-enemy of the Teen Titans, and a powerful villain. He has enhanced physical abilities, a healing factor, high intelligence, knowledge of many styles of martial arts, and is an expert in psychological warfare.
One of the Freelancers, who comes from "somewhere British", as it may be. He lived as a mercenary, offering his services to the highest bidder, until a screw-up with his time-looping ability caused him to almost be killed by Tex, leaving only one copy of himself behind. He entertained thoughts of revenge against Tex and the other Blues, never putting them into action until he learned that Tex had joined Team Paladin, leading him to join the Hellfire Club. Besides being a skilled marksman, he was given an experimental Box Weapon, the Lightning Weasel (experimental because it has a bad habit of spontaneously exploding).
The Flame Alchemist of Amestris. A good man with a great dream for his country...until it all came crashing down around him. Mustang struck a deal with Dr. Tim Marcoh, on his end obtaining a Philosopher's Stone he could use to regain his eyesight (lost as a result of being forced to open the 'Gate of Truth' in the final battle with Father). However, approximately two years afterwards, his world went dark again, without any visible cause. With no sight, he lost all support in his bid to become Fuhrer. It became even worse for him when Slade of the Hellfire Club appeared, and broke Mustang psychologically. Slade then recreated Mustang's mind with the conviction that by turning his back on Amestris, he could become even greater than that. Slade restored Mustang's sight, and Mustang soon after joined the Hellfire Club. Mustang is unaware that it was through Slade's doing that he lost his sight for the second time.
Former member of the Gung-Ho Guns and Wolfwood's old mentor, Chapel was killed by Legato Bluesummers after being forced to kill Wolfwood. In a manner similar to his pupil, Chapel also found himself in an afterlife different from his own, but because of his raw anger, he became a Hollow. Killing and consuming souls, over the course of six months he eventually became a Menos Grande, a powerful Gillian, before being turned into a test subject by Hojo. He was found caged up in Hojo's lab, and Wolfwood drew his zanpakuto to release Chapel from the horror of being a Hollow. But before he could do so, Chapel tore off his mask, turning into an Arrancar. He berated his former student, having become too Hollow-like to remember that he had died trying to avenge Wolfwood. He left a large cut on Wolfwood, and the latter was forced to run.