Tessa lived in a harem in the Balkan region of Europe. In her teenage years, the Russians invaded Afghanistan so she had to learn how to use weapons and fight against soldiers and local bandits. One day, she felt compelled to enter a local cave and found Professor Charles Xavier trapped under some rocks, his legs crushed. Soon after, some bandits who had raped and killed a convoy of U.N. workers attacked them, but Tessa drove them off, killing one of them.
Some time later, Professor X recruited her into the X-Men, but kept her secret so she could use her telepathic power to spy for his fight for peaceful co-existence between mutants and humans. Tessa’s first mission was to infiltrate the Hellfire Club and become Sebastian Shaw’s adviser. Shaw even kept her after his leadership, due to her usefulness of keeping large amounts of information.
Sage was created by Marvel writers Chris Claremont and John Byrne in 1980. She made her first appearance in the comic world in The X-Men # 132.
Tessa was then given the codename Sage by Storm, who recruited her into the X-Treme X-Men who had been set out to search for a mutant named Destiny who could predict the future. On their way, Beast was almost killed by Vargas but Sage used her previously unseen ability to advance his evolution to the next stage.
Shaw found out that Sage was a spy for Professor X and he allied himself with Lady Mastermind, the daughter of Mastermind to plan his revenge. Lady Mastermind created an illusion against Sage, making her believe that she was an assistant for Shaw once more. Sage was freed once again thanks to Lifeguard, a mutant with the ability to use any power, depending on the situation. The X-Men defeated Shaw in the end.
Sage later increased Slipstream’s power and allowed Rogue to control the powers she has absorbed over the years. Sage would also help out Bishop in his other missions.
Major Story Arcs
In the Hellfire Club
Later, Shaw made a poker bet with billionaire Elias Bogan where if Shaw lost, he would have to hand over Emma Frost, though if Bogan lost Shaw would receive his entire fortune. Bogan had never lost a game before, but astonishingly, Shaw won, mainly due to Tessa's help. Bogan knew that Tessa was the one responsible for Shaw’s win and captured Tessa, scarring her beneath the eyes. Abandoned by Shaw, Tessa was saved by Storm, and she joined the X-Men, though she nullified her telepathic abilities to prevent Bogan from finding her again.
When Senator Robert Kelly ran for president, Tessa met with him to persuade him that his actions were no better than those of the mutant terrorists. However, Kelly was not convinced until a mutant saved his life where he realized that some mutants use their power for good.
Later when the X-Treme X-Men encountered Elias Bogan again, Sage and Bishop were called to investigate because of a murder. A mutant called Jeffrey Garrett was wanted for questioning when Bogan killed his family and Garrett teleported Bogan’s associates up to the mountains to freeze to death. Garrett fled to the Xavier Institute, where Emma Frost scanned his mind, and she was now possessed. Sage and Bishop followed the trail where Bogan held them hostage, but Storm arrived just in time to defeat the villain.
Bogan captured and possessed Bishop and would use him as a weapon against his teammates. The X-Men with other allies were able to rescue him, which allowed Sage to defeat Bogan once and for all. Sage helped the X-Men rebuild the mansion after Magneto’s attack, and rejoined them.
After concluding that Destiny's writing on the diaries to be invalid, Tessa joined the X-Treme Sanctions Executive, to monitor mutant relations and activities around the world. She had to end her tenure to the group and join again the Hellfire Club to watch over Sunspot, who had become a high ranking official in the Club, because he might become corrupt with power as Shaw did in the past.
She then left the Hellfire Club to join Excalibur, the mutant team based on Britain. Tessa becomes a spy again in order to get close to Albion, and she develop a new personality, calling herself Diana Fox, who is completely loyal to Albion. She quickly climbed up through the ranks and eventually become one of Albion's elite, the Shadow Captains, and took the name, Britannia.
When she had an opportunity to kill Albion, she didn't take it, and much to the fear of Tessa's Excalibur teammates, her Diana Fox personality now fully control Tessa's body. But when she was confronted by her teammates, Tessa's came back to her old self and quickly defeated Albion and his Shadow Captains.
Excalibur came back to their base and celebrated their recent victory, Sage felt that guilty about her actions. The party was crashed surprisingly by Psylocke and an alternative version of Thunderbird, who are both members of the reality fixing team, Exiles. Then the party was abruptly ended when the Rouge-Mort attack Excalibur. The battle escalated to the point that it will destroy the Multiverse by a psychotic Merlyn with the help of the Fury. When Merlyn stabbed Roma and is now slowly dying, she transferred all her knowledge about the Multiverse to Sage, which almost driven her mad. Fearful of the knowledge she now possessed might fall in the wrong hands, she joined the Exiles to be safe.
Sage continued to struggle with all the information given to her by Roma, and worse it seemed to have given life to the Diana Fox persona. While Sage would time to time gain control over all the hallucination, Diana would continue to be an aggressive force and fight for control. One day while dealing with Cat and her struggle to heal they dying Omniverse the phantoms in Sage's mind broke free.
She sent Cat away and decided to deal with Diana once and for all. During the fight it is revealed that Merlyn has reemerged and is trying to kill Sage, however, Diana sacrifices herself so that Sage can save the omniverse. With Diana reabsorbed and Merlyn defeated, Sage merges with the Crystal Palace enabling her to save creation. From then on when the Exiles communicated with the Crystal Palace, they were not addressing a computer, they were talking to a living being: Sage.
This soon faded though, and all the Exiles absorbed into the walls of the crystal palace and someone else has taken Sage's place. Sage has not been seen since.
Sage is a mutant with a computer-like brain. She can process large volumes of data with efficiency so great it is nearly instantaneous. She also has a photographic memory which allows her to recall almost anything she needs. Sage;s mind also has a reboot function similar to a computer's. Sage's computer intellect has facilitated her ability to learn many things in many fields including advanced martial arts, tactics, and weapons training.
Sage is in peak physical condition and is skilled at both unarmed and armed combat. She is skilled with technology, and uses a set of VR glasses that allow her to interface with computers and other technology. Other people can link up with similar sets of glasses. Sage is often used as the tactician and/or headquarters' hub, using her mind to keep in constant contact with all of her allies at once.
Sage also absorbed all of Roma's knowledge and memories. All of this "information download" happened almost instantly, so her mind turned all of this knowledge into several distinct personalities. She then bested each in mental combat and assimilated them into her memory. Whether or not this granted Sage any of Roma's magical ability is unknown.
She also has the ability to detect and analyze the genetics of others. So far this ability has been used to unlock latent mutant abilities in dormant mutants, and to unlock hidden aspects of mutant powers. This ability works closely with her computer-like mind giving her the ability to quickly analyze and understand the subject's DNA. Sage can also "see" the genetic structure of a person. She can read the DNA and understand their power (If they are a mutant) probably better than the person can themselves. She can then boost the person's powers advancing them to a certain extent. Also she can see the potential in a human to become a mutant and jump start their latent power.
Sage is a telepathic mutant with the ability to read minds, project her thoughts, control minds, project her astral form and project realistic illusions. She is able to sense any form of life near her and especially mutant minds. Also she can reflect telepathic attacks away from her by using her 'Firewall' ability. She can only use this by shutting her telepathic powers off. Sage exhibits strong willpower which protects her from certain telepathic attacks.
- Height: 5'7"
- Weight: 135 lbs (61.2 kg)
- Eyes: Blue
- Hair: Black
- Unusual Features: Sage has distinctive tattoos on her face.
- Known Relatives: No known relatives
- Citizenship: American
- Place of Birth: Balkans Region, Europe
- Marital Status: Single
- Occupation: Adventurer, Former Spy, Detective, Personal Assistant to Sebastian Shaw, Mercenary
- Education: Unrevealed
Marvel Mangaverse (Earth-2301)
In a reality where Marvel Characters are converted into Japanese Manga styled characters, Sage is a member of the Hellfire Club alongside with her father Professor X and her sister Emma Frost. The intention of the club is to have Jean Grey back to the team. However, Toad who was a genius being advised the X-Men about defeating Hellfire Club and have her father back to the X-Men.
What If...? Magneto And Professor X Formed The X-Men Together?
Sage was among the mutants who were trained by Professor X together with Magneto on his side. Sage's powers became very useful for both men for detecting mutants to join the X-Men. Since her powers were enough to locate mutants, Professor X did not attempted to develop the Cerebro, a machine that can also locate mutant brain waves. But when the Professor finally decided creating the Cerebra for wider range of mutant detection, he asked Sage to test the machine. Following some events, she became the Professor's Executive Assistant.
Sage is a member of the X.S.E. Following some events, X-23, Iceman and M were assigned to take Sage into custody. Sage used Malice's choker and attached it to Laura's neck to gather information. Aside from her, Sage also used this equipment to gather more information around the planet. After detaching the equipment, Sage have attempted to escape but Iceman have frozen her with his ability over ice. After the fight, Sage was safely taken into custody.
In the mental illusion created in Prodigy's mind by the combined efforts of Emma Frost and Danielle Moonstar, Sage is the secretary of Prodigy. She was responsible for Jeffrey Garrett's attempt to destroy China. She is also the one responsible for Icarus' death.
X-Men 3: The Last Stand
In the novelization of the move, written by Chris Claremont, Sage is a mutant who became one of the new students admitted to Xavier Institute. Along with Cannonball, Moonstar and Gambit, she was trained by Wolverine.