A novice sorceress, the Scarlet Witch is also a mutant with the genetic ability to warp reality, or to manipulate forms of mystical energy such as chaos magic, or both (accounts regarding the nature of her powers are conflicting and confused). 

     She is a veteran adventurer and longtime Avengers member who joined the team alongside her twin brother, Quicksilver (Pietro Maximoff), when they successfully applied to fill vacancies in the group's ranks created by the departure of the founding Avengers. 

     Apart from one health-related leave of absence (during which their powers temporarily waned), Wanda and Pietro served an uninterrupted membership stint until Magneto briefly duped them into rejoining him. They soon abandoned him again but remained apart from the Avengers for a time, trying to make their own way in the world. The twins eventually rejoined the Avengers, serving another long stint together, but Pietro's close relationship with Wanda soured when she began dating her android teammate Vision against her brother's wishes. Ironically, Pietro began to feel out of place in the team as Wanda grew to feel more at home, even though it was he who had talked her into joining in the first place; he eventually quit the active roster and moved to the secluded Inhuman city of Attilan, where he married the Inhuman adventurer Crystal. Wanda, meanwhile, expanded the scope of her mutant powers (which she had long believed to be probability-warping powers) by studying magic with the sorceress Agatha Harkness, becoming a capable mystic in her own right.

     Against all odds, Wanda formed a strong and lasting romantic bond with The Vision. What she did not know was that their romance was being encouraged and manipulated behind the scenes by the sinister Immortus, a time-warping mastermind who has acted as both friend and foe to the Avengers in the past. Immortus used a series of elaborate and subtle manipulations to encourage the growing romance between Vision and Scarlet Witch, thinking that the Witch's subsequent marriage to the android Vision would eliminate the possibility of her bearing any children (any offspring of the Scarlet Witch are supposedly fated to be among the great powers of the universe, making Wanda and her potential children particularly dangerous in the eyes of Immortus's cosmic masters, The Time-Keepers). Prior to their marriage, Immortus tried to reinforce Vision's sense of personhood through various means, including the revelation of Vision's past life as the original android Human Torch. The discovery that he had a fuller past than he had once believed did indeed make Vision feel more human, and helped give him the confidence to propose to Wanda. The two Avengers were married, and were very happy together for years.

     The first major threat to the Vision-Witch union was a ghost of sorts: Simon Williams, the long-dead Wonder Man. A fallen hero who had betrayed the Avengers to the Masters of Evil and then sacrificed himself to defeat the Masters, Wonder Man had been seemingly dead and gone for years before returning to life through a bizarre set of circumstances and rejoining the Avengers. This was most unsettling for Wanda and Vision, even though they had never met Simon before, because Simon's brain patterns had been used as the template for the creation of Vision's artificial mind. Vision felt insecure about Simon's return since he feared he might be merely a mechanical copy of Simon, and Simon himself was attracted to Wanda since he shared Vision's affinity for her. The awkwardness between the three Avengers persisted until a confrontation with Simon's mad brother, the Grim Reaper, forced Vision to see himself as a unique being distinct from Simon. Vision's marriage to Wanda survived unscathed, and Simon repressed his feelings for Wanda for years thereafter. Eventually, Simon and Vision even formed an affectionate, brotherly relationship, regarding each other as twins.

     Meanwhile, Django Maximoff, the Gypsy shaman who had raised Wanda and Pietro as his adoptive children, had gone somewhat mad from loneliness. He used his gypsy magic to entrap the souls of Wanda and Pietro in dolls so they could not leave him again, but they were freed by the Avengers. The twins forgave Django his desperate act and decided to spend some family time with him anyway, taking a trip to Transia to explore their roots. During this excursion, Pietro and Wanda visited their birthplace, Wundagore Mountain, and met the midwife Bova, who had cared for them as infants; she told them of their true mother Magda's death shortly after their birth, revealing that their biological father was neither Django Maximoff nor Bob Frank, the Golden Age crimefighter and honorary Avengers member known as the Whizzer (for a time, Wanda and the Whizzer had mistakenly believed Frank was their biological father); instead, Bova said, their father had been a dangerous man they were better off not knowing, a man Magda had fled for the sake of her children's safety. Shortly after returning to Transia, the adult Wanda was possessed by the elder demon Chthon, which had formerly been trapped in Wundagore Mountain. Working together, Pietro, Django and the Avengers managed to cast Chthon out of Wanda's body and trap the demon in one of Django's dolls, which was then buried in an avalanche on Wundagore Mountain. Django died during the battle and was mourned by his adoptive children, who soon learned that their true biological father was their old tormentor Magneto. Despite this revelation, the twins' relations with Magneto have remained tense at best, and often hostile.

     Yearning for a normal family life, Wanda convinced Vision to join her in retiring from the active Avengers roster and buying a house in Leonia, New Jersey, only to see it burned down by bigoted neighbors. The couple also found themselves repeatedly called back into Avengers service, including a mission during which Vision was rendered inert by Annihilus's null field. The Avengers restored Vision to consciousness and mobility by linking him with the Titanian supercomputer ISAAC; but unknown to the team, ISAAC had a dangerous influence on the android Avenger, programming Vision to take control of Earth's computer systems just as ISAAC dominated Titan's computer systems. Vision did indeed briefly seize control of the world's computer networks and plotted to establish himself as a benevolent dictator of sorts, but he relinquished control after Wanda and the other Avengers helped him shake off ISAAC's influence.

     Despite Vision's swift abandonment of his world conquest attempt and the revelation that he was not responsible for his actions, the U.S. government was extremely suspcious of Vision thereafter, and government harassment of the android prompted him and Wanda to quit the Avengers altogether for a time. Returning to Leonia, they bought a new house and made a new start as a quiet suburban couple, occasionally becoming involved in various adventures despite themselves. Their greatest adventure proved to be parenthood, though, after Wanda's magical powers made it possible for her and Vision to conceive: nine months later, Wanda gave birth to twin sons, Thomas and William Maximoff. Vision and Wanda were overjoyed at becoming parents, a joy only slightly diminished when a major membership walkout pressured them into joining the short-handed western Avengers roster shortly thereafter.

     When the Vision-Witch marriage produced children after all, Immortus acted swiftly to destroy them. He manipulated the world's governments, already suspicious of the Vision, into forming a global coalition of intelligence agencies dedicated to neutralizing the android. Duping the estranged Avengers member Mockingbird into serving as an unwitting accomplice, this intelligence coalition kidnapped Vision, dismantled him and erased his mental programming, seemingly destroying his unique consciousness and personality in the process. The Avengers managed to rescue and reconstruct the Vision, but he now behaved like an emotionless robot. To make matters worse, Wonder Man refused to assist in attempts to restore Vision's mind since he still secretly wanted Wanda for himself.

     Devastated by Vision's pseudo-death, infuriated by Simon's betrayal and frustrated by the Avengers' inability to restore The Vision, Wanda began to descend into madness, a descent made swifter when two different would-be world conquerors--That Which Endures and the Deviant high priest Ghaur--each used her as a brainwashed pawn on two separate but almost consecutive occasions. During these events, Immortus further eroded the Witch's grip on reality and her faith in her family by hoaxing the Avengers into believing that Vision might not be the reconstructed Human Torch. Immortus also used the Forever Crystal to create an exact temporal duplicate of the Human Torch during the time period shortly before the Vision's creation, so that one Torch was rebuilt into the Vision by Ultron and another Torch was buried by the Mad Thinker as part of an unrelated scheme. Immortus then planted clues which led the present-day Avengers to find and revive the duplicate Torch, seemingly proving that Vision had never been the Torch. With her husband's mind erased and his entire history called into question, Scarlet Witch's mental and emotional bond with her mystically conceived children began to weaken, just as Immortus planned. The boys began to fade out of existence whenever Wanda was not with them or thinking of them.

     Finally, Wanda's twins were abducted by the malevolent mystic Master Pandemonium, who mistakenly believed the boys were formed from fragments of his own splintered soul. In fact, Tommy and Billy proved to be reconfigured fragments of the power of the demon lord Mephisto, who had tricked Pandemonium into locating portions of Mephisto's lost power in the belief that he was pursuing fragments of his own lost soul. Since Wanda's bond with the boys had already been weakened, Mephisto was able to absorb Tommy and Billy and reconvert them into aspects of his power, effectively killing them.

     With Wanda's marriage and her children both destroyed, Immortus's plan had succeeded. As an added bonus (from Immortus's perspective), Wanda's mind had snapped in the process. Suffering a complete mental collapse, Wanda went through a brief period of criminal insanity during which she renewed her alliance with Magneto and battled the Avengers as his partner. Her brother Quicksilver and the other Avengers managed to separate her from Magneto, but the mentally exhausted Wanda was then abducted and enslaved by Immortus, who planned to use her powers as a tool to further refine his manipulations of the timestream. Aided by Wanda's old mentor Agatha Harkness, Pietro and the other Avengers managed to help Wanda shake off Immortus' influence and regain her sanity.

     After a period of rest and recovery, Wanda returned to the active Avengers roster, operating out of the team's west coast base (the still-robotic Vision, by that time, had moved to the team's east coast base, seemingly indifferent to Wanda's continued existence). Gradually accepting the fact that her marriage to Vision was effectively dead, Wanda threw herself into Avengers work to forget, discouraging the romantic advances of her lovesick teammate Wonder Man. Eventually, Wanda was even elected leader of the team's western roster, though her leadership stint proved brief and disastrous. Mockingbird was killed while pushing Scarlet Witch and Hawkeye to safety during a battle with Mephisto, Hawkeye left the team to mourn her death, War Machine quit during an angry argument with Iron Man, and the remaining western roster was disbanded during a dispute with the eastern faction of the team.

     Embittered, Scarlet Witch accepted Iron Man's offer to join and lead a new team he would found and finance, a group called Force Works. This new group was mildly successful for a short time, but it was troubled by an external rivalry with the Avengers and an internal rivalry between Iron Man and Scarlet Witch, not to mention the apparent death of Force Works member Wonder Man during the new group's first adventure. When Iron Man went mad and seemingly died during the events of The Crossing (another elaborate hoax perpetrated on the Avengers by Immortus), Force Works broke up and Scarlet Witch rejoined the Avengers. By that time, Vision had regained a semblance of his original personality and began seeking a reconciliation with the Scarlet Witch, but she was wary of being hurt again and rejected his various overtures.

     When most of the active Avengers (including Vision and Wanda) were seemingly destroyed in battle with Onslaught, they actually surived by being displaced into an alternate reality, where they were trapped for months. When the displaced Avengers returned to their own world, Vision and Wanda were among the heroes who helped rebuild the Avengers (which had broken up in their absence), also participating in the team's battle with Morgan Le Fay. During this conflict, Wanda developed a greater facility for manipulating magic, Wonder Man was resurrected as a ghostly energy being through the power of Wanda's sorcery, and Vision was badly injured (his entire lower body blown away) as a result of Wanda's hesitation to use Wonder Man as a weapon against Morgan. Finally driven to act by Vision's mutilation, Wanda defeated Morgan, but Wonder Man was seemingly destroyed again in the process.

     These events came back to haunt Wanda, both figuratively and literally. Feeling guilty about Vision's mutilation, Wanda tried to comfort him and tentatively explored the possiblity of a reconciliation with him; but Vision, not wanting her pity and by now convinced that Wanda would be better off without him, pretended that he was emotionally indifferent to Wanda once more, and said her obligations to him ended when he "died" during his deconstruction and reprogramming. Confused and hurt, Wanda gave up on Vision, and the ghostly energy wraith Wonder Man had become began mainfesting in Wanda's vicinty whenever Simon felt Wanda needed him, or whenever Wanda summoned him. At first unsettled by this strange link with Simon, Wanda soon began to revel in it after sharing a night of passion with the ghostly Simon. Regardless, she remained uneasy about how and why Simon was appearing in this fashion, and wondered if there was anything she could do to restore him to true life.

     Upon consulting her mystic mentor Agatha Harkness, Wanda learned that, as a result of her birth on the Chthon-possessed Wundagore Mountain, her mutant power was not probability-warping (as she had always believed), but was instead an instinctive mutant ability to tap and manipulate the forces of chaos magic. Knowing this, Wanda became more powerful than before. Agatha also explained that Wonder Man's ghost was bound to Earth by his love for Wanda, and that Wanda could only fully restore him to life by returning that love. Initially unsure if she was capable of loving Simon, Wanda examined her feelings for him and did indeed find it within herself to love him, with a passion she had always repressed and denied because of her previous love for Vision. Through her magic and her love, she restored Simon to life and began a romance with him.

     Wanda's romance with Simon was somewhat rocky, due largely to Simon's feelings of guilt over his many real and imagined misdeeds and failings. Simon felt inadequate next to many of the other Avengers, especially Vision, whom Simon regarded as a superior version of himself. Simon also felt guilty about coming between Wanda and Vision, though Wanda urged Simon not to worry about that, and remained devoted to Simon even after discovering that Vision still loved her. Wanda even encouraged Vision's romantic interest in other women such as Warbird and Mantis, despite her own feelings of jealousy regarding these developments. At the same time, Wanda worked to master the expanding range of her powers, and began to take a more active part in Avengers affairs, serving as deputy leader.

     The Wanda-Simon romance became a long-distance relationship after he opted for reserve membership and relocated to California, where he now devotes most of his time to the activities of his Second Chances charitable foundation. By the time the global Kang Dynasty conflict brought the couple back together, their time apart had forced them to realize they were no longer in love with each other, that they regarded each other primarily as friends, and that their affair had stemmed more from passion, loneliness and a sense of obligation than true love. Wanda even admitted that she was still in love with the Vision, though she had no expectations in that regard since he had finally moved on. Regardless, Scarlet Witch and Wonder Man are once more friends and teammates rather than lovers, and Wanda began trying to get close to the Vision again while they served together as active Avengers. Quicksilver and the Scarlet Witch also learned they had another sibling when X-Men veteran Polaris was revealed to be Magneto's daughter.

     Wanda's life took a bizarre and tragic turn when she went mad again, apparently a delayed reaction to the loss of her children; apparently, at some point she had edited their existence and fate from her memories to spare herself pain, but the memory resurfaced and she slowly, secretly became criminally insane. More powerful and more dangerous than ever, she began warping reality and eventually snapped altogether, wrecking Avengers Mansion and apparently causing the deaths of teammates Jack of Hearts (a recently deceased Avenger whom she reanimated to serve as a weapon), Ant-Man (Scott Lang), Vision and Hawkeye. While aiding the Avengers against Wanda, the sorcerer Doctor Strange claimed that there was no such thing as the chaos magic Wanda supposedly manipulated, and that Wanda had been subconsciously using her mutant powers to warp reality in various ways for years, notably by mystically resurrecting the deceased Agatha Harkness to serve as her advisor when she began to lose her children. When Doctor Strange finally defeated Wanda by shutting down her mind, Harkness reverted to a long-dead corpse. Wanda's father Magneto took custody of the catatonic Scarlet Witch, housing her in Genosha, where Magneto's associate Professor Xavier tried to heal her mind.

     Gradually determining that Wanda's sanity was beyond repair and that her power was beyond containment, Xavier led the Avengers and the X-Men in discussing what to do with Wanda, even considering killing her for the safety of the world. Horrified by this and trying to protect his sister, Quicksilver pushed Wanda to use her powers to reshape all existence into the "House of M" alternate reality, a mutant-dominated world where a seemingly human Wanda led a peaceful existence. Among the many other changes in her subconsciously idealized world, Wanda resurrected Hawkeye, though she seemingly unmade him again when he turned against her. As the "House of M" reality degenerated into deadly conflict between various factions, Wanda restored conventional reality, albeit with one key alteration: apparently having decided that mutants were the source of all her woes, Wanda decreed "no more mutants" and tried to transform all of the world's mutants into ordinary humans. For the most part, she was successful: only a tiny minority of the world's former mutant population retained their powers, while most of the rest (including her relatives Magneto, Quicksilver and Polaris) were depowered. Unknown to her enemies, Wanda herself is currently living a peaceful civilian life in an undisclosed location, though the state of both her powers and her sanity is currently unknown.

     Evidence has recently come to light indicating that two members of the teenage Young Avengers super-team, Billy Kaplan and Thomas Shepherd, may be the Scarlet Witch's lost children, who were apparently somehow reincarnated or resurrected in the past and grew up to be young adventurers. Whether this is true and how it will affect the Scarlet Witch remains to be seen.