Sage's exact country of origin remains unrevealed, but she claims to have come from a war-torn region. By the time she reaches young adulthood, she is living by herself in the Balkans. Although she tries to keep out of the conflicts between the rebels and the government, she is willing to use her guns and other weapons on any threat. One day, she feels herself called to a cave which was considered haunted by the locals. She hears a voice in her head that guides her deeper into the cavern, where she finds Charles Xavier, who is trapped underneath a pile of debris. His legs have been crushed during his battle with the alien Lucifer. Xavier senses that Sage is a mutant, and explains to her what her abilities mean. Sage helps Xavier and tries to get him to a hospital, but during their journey down the mountains they come across a United Nations relief convoy under attack by robbers, who have raped and killed the UN workers. Sage exacts revenge on their behalf and kills the robbers, though she despises herself for being so brutal.
The Hellfire Club
Years later, Sage meets up again with Xavier, who at the time is recruiting the original X-Men. Instead of having her join them, he trains her in secret as a spy. He sends her to the Hellfire Club to keep watch on Sebastian Shaw. While working there, she encounters Psylocke and Jean Grey, as well as Emma Frost, who at this point is the White Queen. While she is able to successfully warn Psylocke away from the Hellfire Club, Sage is later remorseful that she is unable to similarly prevent the corruption of Phoenix into the Black Queen. This transformation is a key factor, ultimately, in the creation of Dark Phoenix. Sometime during Sage's time with the Hellfire Club, Sebastian Shaw and Emma Frost dare the man known as Elias Bogan to wager in a game of poker. Though he holds no official rank in the Inner Circle, the telepathic Bogan is one of the Club’s most important and powerful members; his patronage guarantees success in the organization. By the terms of the wager, if Shaw loses, Frost would "belong" to Bogan, but if Bogan's agent loses, then his fortune would be turned over to Shaw. Mostly due to Sage’s advice and analytical skills, Bogan loses the game and is forced to honor the wager. Having never lost before, Bogan harbors a grudge against Sage.
During the X-Men's initial conflicts with the Hellfire Club, Sage maintains primarily a background role and is seen as only Shaw's unusually intelligent assistant. Hints of her more complex role are indicated when she and Xavier are kidnapped by Donald Pierce, a renegade member of the club, with grudges against both organizations. Based on the interactions between Xavier and Sage, it is unclear whether he is helping to maintain her cover or whether he feels as if he has lost his agent; the interaction between the two is cold and apparently antagonistic. The two are rescued by the nascent team of New Mutants, and Sage takes Pierce into custody on behalf of the Hellfire Club.
Sage's next notable interaction with Xavier's students happens months later when the X-Men and Hellfire Club are hunting down Rachel Summers after her attempted murder of Selene, the newly installed Black Queen. In the middle of their fight, both teams are taken by surprise by Nimrod, a mutant-hunting robot from the future. Recognizing the more immediate threat, the two groups join forces and are able to severely damage Nimrod. The X-Men and Hellfire Club each sustain heavy losses and are forced to flee the scene quickly. Sage offers Storm and the X-Men temporary sanctuary with the Club, which later results in Magneto and Storm jointly accepting the role of White King in the Inner Circle.
After Hellfire Club
Magneto becomes more actively involved with the Hellfire Club after the X-Men's supposed death in Dallas at the climax of the Fall of the Mutants. Tensions between Magneto and Sebastian Shaw grow until, finally, Magneto ousts Shaw from the group. Although Sage remains with the Hellfire Club after his departure, her role diminishes. Shortly thereafter, the Upstarts begin hunting down mutant leaders, starting with former and current leaders of the Inner Circle. Shinobi Shaw seemingly murders his father, Sebastian; Emma Frost is put into a coma. Sage continues to serve as Shinobi's assistant, much as she had with his father and she also begins using her telepathic skills more openly. After Sage prevents Shinobi from solidifying his hold on the Hellfire Club, however, the younger Shaw ceases working with her.
Sebastian Shaw returns after a period of recuperation with the extradimensional Holocaust at his side. Seeking assistance in controlling this powerful mutant, Shaw calls Sage back into his service. Her minor telepathic abilities are able to keep him in check since most telepaths in his native reality had been killed and he had not developed psychic defenses. The two lose Holocaust, though, when Onslaught decides he needs that mutant for his own purposes. Selene and her new amnesiac thrall Madelyne Pryor join with Shaw to regain their roles in the Hellfire Club. Suspicious of Pryor, Sage attempts to telepathically probe her while she is sleeping. Unwittingly reawakening Madelyne's memories of her tragic life and first death with the X-Men, Sage is quickly overwhelmed and nearly killed. The only thing that stays Madelyne's hand is that Sage's murder would have caused unnecessary complications. Instead, Pryor merely removes all memory of the conflict.
For reasons yet unknown, Sage leaves Sunspot's side and travels to England to join forces with the newly reformed New Excalibur. She helps them on various missions such as battling the Shadow King and returning to ancient Camelot to prevent it from being prematurely destroyed. In a more subtle use of her observation abilities, Sage is instrumental in her teammate Nocturne's recovery from a debilitating stroke. In order to learn more about a mysterious new foe, Albion, and thwart his attempt to conquer Britain, Sage creates the new cover identity and persona of Diana Fox. This persona appears to be fully devoted to Albion and his goals. However, this bothers her teammate Wisdom as he fears she might fail the mission similar to her time with the Hellfire Club. Her Diana Fox persona climbs up the rank of Albion's Shadow Captains as Britannia and develops a rivalry with Lionheart. Like the rest of Albion's army, Sage is given a suit that emphasizes loyalty to him, as well as equips her with flight and super-human physical strength. Although she has the opportunity to kill Albion, one purpose of her infiltration, she is struck by an errant pulse from an ancient item used by Albion to extinguish power in England. Though Lionheart suspects her betrayal, Albion believes she was only trying to protect him. Wisdom's fears are realized after this when the Diana Fox persona takes complete control and Sage becomes fully committed to Albion's side. During this time, she slays two of New Excalibur's erstwhile allies in Shadow-X, Dark Cyclops and Dark Beast. A direct confrontation with her teammates in New Excalibur help reassert Sage's original personality. Together with New Excalibur, Shadow-X, and now heroic Lionheart, Sage defeats Albion and his Shadow Captains.
Immediately after the defeat of the Shadow Captains, a party is held in honor of Excalibur. While the team enjoys the party, Sage feels guilt for her actions. The party is suddenly crashed by Psylocke and an alternate universe Thunderbird, members of the Exiles. They are then attacked by Rouge-Mort and drawn into a battle for the safety of the Multiverse from a psychotic Merlin and The Fury. They join forces with the rest of the Exiles, Roma and the Captain Britain Corps. The team defeats Merlin, but not before he manages to kill Roma. Prior to her death, Roma manages to transfer all of her knowledge about the Multiverse into Sage's mind, causing her to become overwhelmed; she fears for her sanity. Fearful of what would happen if someone on Earth ever gained the knowledge in her mind, Sage joins the Exiles. She currently suffers from hallucinations mixing her own memories with the information passed to her by Roma; furthermore, the Diana Fox persona has re-emerged and is attempting to take control once again. While the other Exiles go on missions, Sage largely remains back at their base of operation, fighting the effects of Roma's memories and Diana Fox tenaciously every day until she drops from exhaustion. She refuses to lose possession of her mind, body, and soul. For a while she manages to calm down the phantoms, however, Diana Fox remains an aggressive presence in Sage's mind, fighting her for control. While diverting her focus to analyze Cat's uncontrolled ability to "cascade" through different alternate versions of herself, and Cat's empathic connection to the Crystal Palace, the phantoms in Sage's mind break free from their mental prison. Sage decides to confront them and Diana once and for all. During her struggle she bonds with Cat, who had been trying to find a way to heal the dying Multiverse. Sage tells Cat that she is probably too close to the situation and that it is time for a fresh mind and a new perspective. She sends Cat away to join the rest of the team and prepares to find answers, just as Diana Fox shows up, wanting to fight. Sage and Diana fight each other but neither is yielding; they are too evenly matched and equally stubborn. As long as they fight each other, they can't defeat the phantoms. The women decide to team up against a greater threat: the return of Merlin. During battles, Sage and Diana get a better understanding of each other and their motives. Merlin almost kills Sage. Knowing that she could never find answers the way Sage could to the collapsing of the Multiverse, Diana decides to sacrifice herself to revive Sage for the greater good. Sage reabsorbs Diana and destroys the evil version of Merlyn. Sage then follows her instincts and merges with the Crystal Palace, an act which stabilizes the Multiverse. This fate was intended for Cat, but she was too young and too scared; she couldn't handle it. From now on when the New Exiles communicate with the Crystal Palace, they are not addressing a computer, they're talking to a living being: Sage. Sage was seen once more in the Crystal Palace. However she seems to have been permanently absorbed and rendered comatose along with her Exiles team. If she can be revived, separated, or if she is going to be seen again remains unknown.
Powers and Abilities
Cyberpathy: Ability to interface and communicate with computers, computer mainframes, and any data processors at a speed that's equal to, if not greater than, that of the computer itself. She can also send e-mail using only her mind. She is generally always in contact with her cybernetic shades, which itself is connected to a super-computer. Kinetic Memory (Computer Brain): Her mind works in the same way as a computer with unlimited storage capacity, only much faster. She is able to perform several mental functions at once without losing focus on any of them. Also, allows her to instantly recall specific information with incredible speed and accuracy. She's able to store everything that she experiences in a photographic memory and retrieve it immediately without the typical human pause for thought. The sheer speed of her thoughts lead into augmenting her analytical ability so that she is able to make snap decisions about her surroundings and create complex scenarios at that same speed. As such, Sage is able to track the probability of an event by piecing together stored data.
- Multi-tasking: Able to perform multiple tasks at once by allocating a partition of her brain to each task. For example, Sage can use her mind to replay a movie she had watched previously, play a game of internet chess, and focus on battling an opponent without any one task distracting her from another.
- Firewall: possesses protection against telepathic attacks. Achieved this state only by permanantly shutting down her own low-level telepathic abilities.
Genetic Sight: able to 'see' a person's genetic code, reading complex DNA sequences for latent and manifested mutations, thereby allowing her to sense mutants and, in many cases, understand how their powers work more thoroughly than they themselves do.
- X-Factor Sense: ability to sense the presence of the mutant gene in others who are in close proximity to herself.
- Jumpstart: After analyzing the DNA of another superhuman mutant, Sage is able to selectively evolve their existing genetic traits as well as catalyze the untapped genetic potential of latent mutants. Once begun, the procedure is irreversible and can often result in unpredictable side effects.
Telepathy: low-level telepathic talents allow her to communicate with others over short distances and release an astral form within a limited range. She has permanantly shut down her telepathic abilities to protect herself from Elias Bogan.
Sage is skilled in the martial arts, and is a formidable hand-to-hand combatant thanks to her having complete conscious control over her own body. Sage is also self-taught in a wide range of firearms, which she can use with considerable skill and accuracy. She is also exceedingly smart. Her computer mind makes it easy for her to learn new talents.
Cybernetic Sunglasses: Sage wears a pair of custom-built cyber shades that function as a wireless broadband computer network amongst like models. The shades provide an audio/video feed via an in-built computer system outfitted with miniaturized conventional microphones and cameras, and can also project a three-dimensional image into the visual field of the wearer that can be expanded to allow others to see with whom the wearer is communicating or information they are reviewing. The shades provide input by means of a virtual reality iconographic keyboard, and have an alternate visual input system for when a user’s hands are otherwise occupied. The shades can be interfaced with any external data network whether terrestrial or alien in origin. The shades also possess various sensors for detecting telepathic resonance patterns, tracking energy trails, and analyzing electronic circuitry, amongst others.
Sage wields a pair of handguns that fire non-lethal projectiles. Guns and knives.
Sage has a pressure point on her body the allows her to reboot her mind like a computer.