- —Fabian Cortez[src]
Upstarts and Acolytes
Cortez was bored with his life, even though he was wealthy and had high social status. He joined the Upstarts for excitement, a group of mutants organized by the Gamesmaster who were awarded points for killing other mutants. Cortez gathered a group of mutants who believed in Magneto's teachings and formed the Acolytes. He brought the group to Asteroid M, Magneto's orbital base, only to arrange for its destruction and the death of the first wave of Acolytes along with their messiah.
Obtaining many points for the deaths of such powerful mutants, Cortez then gathered a second group of Acolytes easily by playing Magneto off as a martyr. Neophyte overheard Cortez telling the Gamesmaster about how he killed Magneto and caused the other Acolytes to abandon him.
When Magneto returned and was mind-wiped, the Gamesmaster stripped Cortez of his points. Furious, Fabian concocted an elaborate scheme to regain them. He kidnapped Luna Maximoff, the daughter of Quicksilver and granddaughter of Magneto, and began a civil war on Genosha by encouraging mutates to kill the ruling humans. Both the X-Men and the Avengers tried to stop him, and he was apparently killed by the new Acolyte leader Exodus.
Cortez resurfaced months later when Joseph assumed control of the Acolytes. Pretending to help Joseph assume Magneto's leadership role, his schemes were again unveiled. He then tried to destroy the X-Men with another wave of Acolytes, but eventually abandoned his own allies.
Later when Magneto was returned to his full mental capacity, he gave Cortez a chance to redeem himself. Weakened by trying to manipulate the Earth's magnetic field, Magneto needed Cortez's powers to keep him rejuvenated. Magneto offered Cortez a place on the Genoshan cabinet, which he accepted. When Magneto attempted to obtain technology from Carrion Cove that would return his power levels to normal, Cortez betrayed him and helped the United Nations by augmenting rogue Acolytes to fight Magneto and his mutate army. His power levels faded during the battle for Carrion Cove, while Magneto returned to full power. Magneto finally got his revenge and used his new strength to repel Cortez fifty miles and smash him into the ground; he died on impact.
Cortez was resurrected via the Transmode Virus during the Necrosha crisis and, searching for Magneto with his fellow acolytes Delgado and Mellencamp, battled Deadpool and Loa. They were eventually, and contrary to the other "zombies" who weren't killable, killed by Loa's powers as Loa was used as a projectile by Deadpool.
Upstarts v. X-Men v. O.N.E.
Cortez reappeared once again as a member of the mutant group the Upstarts. He helped kill the Nasty Boys in order to lure out Cyclops and his ragtag team of X-Men to Washington Heights. After a brief moment of words, the two groups engaged each other in battle. Cortez faced off against Hope Summers and the Juggernaut but became overwhelmed as they were outnumbered. He fled the scene with Siena Blaze and Fitzroy leaving Shaw behind as a scapegoat.
He was the last of the Upstarts alive. The X-Men bailed him out to help. He used his powers to help the Black Queen remove mutants from the minds of every person. It was revealed that O*N*E had not forgotten about mutants. Their sentinel squad came and started attacking. After many casualties, they shot and vaporized Cortez into nothing, which killed him.
House of X
Cortez was later seen resurrected and well among Exodus and other Acolytes when they were first greeted by a hologram of Professor X, then later when they were seen on Krakoa among other X-Men villains and foes. As Professor X's hologram was conversing with them, around the world he was also greeting and conversing with other mutants, welcoming them into the country of Krakoa.
Cortez later appeared as a member of The Six, a mutant sub-team under the command of S.W.O.R.D. and its commander Abigail Brand. He was the "head" of the mutant power amplification and unification, under the guise of The Power. During the attack of Knull on Krakoa, he headed with other S.W.O.R.D members to defend Krakoa as he gained access to the island by possessing the body of Kid Cable. As he saw Sunfire break both his legs from a great fall after attacking a Symbiote Dragon, he healed him and greatly enhanced his powers, only for Knull to kill them both for their transgressions against him.
He was later revived with the help of Jean Grey, nude and confused he remembered he requested a meeting with Magneto and the Quiet Council (with Brand and Peepers sitting in). After he discussed his views on the law against murdering Flatscans being a waste of not showing mutant superiority, he soon came to realize through their comments and questions that they were just humouring him and didn't take him seriously. Lashing out, he mentioned how vital he was to S.W.O.R.D and how he should be treated better, only for Amelia Voght and Khora of the Burning Heart to teleport in and announce Khora as his replacement.
Still hoping to find a way to break the law against killing humans without getting into trouble, he took Gorgon who had come back from his death in Otherworld not in the right frame of mind, to Central Park and amplified his telepathy so he could hear every negative and hateful thing the people around him where thinking. He almost succeeded in getting Gorgon to kill everybody there but Knightcrawler prevented this by teleporting into an ice-cream stand, making everybody laugh. This allowed the confused Gorgon to calm down and he started serving humans Ice-Cream much to Fabian's dismay. Fabian begged Nightcrawler not to report this to The Quiet Council but instead Kurt dragged him to Planet Arakko and forced him to confront one of his former victims, Lost who's parents were killed in an attack by the Acolytes.
Powers and Abilities
Power Augmentation Manipulation: Cortez had the ability to augment the powers of other mutants, often to dangerous levels. Cortez could also use his power to read genetic code and harm other mutants while appearing to heal them. Fabians powers also lets him make his power augmentation addictive if he so chooses. He also has some control over his own power's energy field, being able to constrict it around a foe.
- Power Siphoning
Fabian was an experienced leader and a skilled martial artist.
Cortez possessed the normal human strength of a man of his age, height, and build who engaged in intensive regular exercise.
- In Magneto: Dark Seduction #4 an image of Mr. Sinister hovers over Fabian Cortez. This may imply that Mr. Sinister played a role in Cortez’s unexplained recovery from his previous death at the end of the Bloodlines crossover in Avengers #369.
- Fabian is a big fan of Dazzler.
- Fabian is a self-proclaimed banjo player.
- Fabian has a Magneto fetish, as he wanted a woman he was trying to have sex with wear a replica of Magneto's Helmet 
- 61 appearance(s) of Fabian Cortez (Earth-616)
- 4 minor appearance(s) of Fabian Cortez (Earth-616)
- 3 mention(s) of Fabian Cortez (Earth-616)
- 29 image(s) of Fabian Cortez (Earth-616)
- 3 quotation(s) by or about Fabian Cortez (Earth-616)