When a top-secret program attempted to recreate the original Weapon X experiment that involved the feral mutant Wolverine, they failed to secure a test subject who could survive the bonding process of the virtually unbreakable metal Adamantium to their skeleton. Seeking to take the project in a new direction, the project's director, Doctor Marin Sutter, recruited renowned mutant geneticist Doctor Sarah Kinney and tasked her with creating a clone.
Using the only available genetic sample from Weapon X, which was damaged, they were unable to salvage the Y chromosome after twenty-two attempts. Kinney proposed they create a female clone, and though her request was initially denied, she still went ahead and produced a viable female subject, prompting Sutter to reconsider. Despite resistance from his protégé Doctor Zander Rice, whom Sutter had raised after Rice's father had been killed by a bestial Wolverine at the original Weapon X Project, Sutter allowed Kinney to proceed. As revenge for her insubordination, Rice forced Kinney to act as the surrogate mother for the clone, and she gave birth to "X-23."
Raised in captivity, X-23 was trained to be a weapon. Kinney did her best to ensure the child retained some semblance of humanity, but her efforts appeared to be in vain. After seven years, Rice had X-23 subjected to radiation poisoning in order to accelerate the activation of her mutant gene, and forcibly extracted her claws and coated them with Adamantium. At one point Rice introduced her "Handler", Kimura, would punish her when she did wrong. Next, Rice created a chemical compound he called "trigger scent" that sent X-23 into an involuntary berserker rage upon smelling its presence. This "trigger scent" was tested on X-23's master, one of few people who treated her with kindness. X-23 was forced to kill her master in berserker rage -- Kimura punished X-23 for this. Three years later, X-23 was sent on her first field mission to kill Presidential candidate Greg Johnson. She was assigned the mission as somewhat of an "advertising" ploy. Numerous other missions followed, as X-23's services were sold to the highest bidder. She was left emotionally stunted as a result. Her missions took her to locations all over the world, including Saudi Arabia, Las Vegas, Japan, Colombia, the Congo, and many others. For one mission she was assigned to pose as the Kingpin's daughter and kill the ones who had captured her, bringing the head of their leader back. Rice, in an attempt to avenge his father's murder, abandoned X-23 on a particularly dangerous mission, but she survived against overwhelming odds and managed to return to the facility. After her return to the facility Kimura punished her for not coming back with Rice.
Sarah Kinney let her out once, not as an attempt to escape but instead to use X-23 to help her find Kinney's niece, Megan, who has been kidnapped. X-23 found and rescued her with ease. Ultimately, Rice persuaded Sutter to hand control of the program over to him, then secretly ordered X-23 to kill Sutter and his family. X-23 was able to kill Sutter and his wife but was unable to kill their son. Instead, she let him live. Later, Rice revealed to Kinney a chamber with dozens of incubation pods containing female clones before he fired her. Before fleeing the facility with X-23, Kinney gave her one last mission - destroy the pods and kill Rice. However, Rice was able to exact revenge on Kinney from beyond the grave, as he had earlier exposed her to the trigger scent, sending X-23 into a rage that caused her to kill her mother. As she lay dying, Kinney named X-23 "Laura".
X-23 traveled to San Francisco and tracked down Megan and Debbie (her mother's sister). Introducing herself as Sarah's daughter, she moved in with them. Although Megan experienced vivid nightmares of her abduction, her family believed these to be utter fantasies. X-23 informed Megan that the man in her nightmares was indeed real and that she had killed him.
Debbie's boyfriend turned out to be an agent for the Facility who had been instructed to manipulate X-23 into killing Megan and Debbie using the trigger scent. However, the agent fumbled the assignment and was killed by X-23. Facility agents stormed the house, led by Kimura. X-23 managed to get Megan and Debbie to safety by handcuffing Kimura to a radiator and then triggering an explosion in the house, buying some time. After X-23 and Megan parted, X-23 decided to confront the man who made her creation possible -- Wolverine.
X-23 tracked Wolverine to Xavier's mansion and engaged him in a battle, defeating him via tactics and maneuverability. However, she did not kill him. Instead, she told him why she had come. Wolverine revealed that he was aware of X-23's ordeal, having received a detailed letter from her mother. The talk was interrupted when Captain America came to arrest Laura.
As a captive of S.H.I.E.L.D. Laura was interrogated by Captain America and Matt Murdock. Despite the mayhem in her past, Matt Murdock accepted X-23's innocence. Captain America wanted X-23 to atone for the murders she had committed. However, he ultimately freed X-23 in order to avoid S.H.I.E.L.D.'s exploitation of her as their own weapon.
X-23 surfaced in New York two years later and was found living on the streets by a pimp named Zebra Daddy, who took her in and employed her as a prostitute. X-23 met Kidon Nixon, a young mutant with the ability to freeze time when in danger. Together with Kiden's teacher, they rescued another young mutant, the feral Catiana, from an angry mob. Zebra Daddy tracked X-23 down, but with the aid of her newfound friends and the mutant named Felon, Zebra Daddy's thugs were defeated. X-23 killed him to save the lives of her friends.
X-23 later took a job at the mutant-themed Wannabee's nightclub in the Mutant Town district of New York. It was there that she saved the life of the daughter of mob boss Don Parisi from a gang of thugs, whom she killed. The deaths inadvertently implicated Wolverine, prompting his teammates in the X-Men to investigate. X-23 instinctively attacked Wolverine on sight, but he was eventually able to calm her down. She led the X-Men to Parisi's daughter. After aiding the X-Men against Parisi's super-strong mutant enforcer Geech, X-23 fled the scene. She later returned to help the X-Men save victims of a car accident, after which she was enrolled at the X-Men's Xavier Institute.
X-23 quickly became very protective of Wolverine, attacking his teammate Bishop after he felled Wolverine during a training session. She also took to observing Wolverine on the mansion's security monitors. During one such viewing, an anomalous energy spike prompted X-23 to investigate. Encountering Spider-Man (Peter Parker) at the source of the signal, X-23 initially mistook him for an enemy and attacked. The pair ultimately teamed up to save the young mutant Paul Patterson from an alternate reality version of the armored Avenger Iron Man (Tony Stark). The arrival of the heroic Captain America and the super-spy Black Widow helped turn the tide.
X-23 secretly followed Wolverine on his investigation of strange activity in the Canadian Rockies. Ambushed by the Hauk'ka, evolved Saurians from the Savage Land, X-23 managed to escape and alert the X-Men. Traveling to the Savage Land, X-23 and the X-Men teamed with the Land's lord Ka-Zar and his circumstantial allies, the Savage Land Mutates, to prevent the Hauk'ka from destroying human civilization by controlling the weather-manipulating X-Man Storm.
Sometime later, X-23 was approached by the cosmic Uni-Power in hopes of making specific use of her healing ability. Although she initially resisted its attempts to bond with her, and she remained reluctant even though it pleaded with her. She ultimately agreed to aid it and became Captain Universe for a brief period of time.
New X-Men After M-Day, X-23 was one of the few students who hadn't lost their powers. The depowered students and staff were sent home; however their bus was bombed by anti-mutant religious zealot Reverend William Stryker and his Purifiers. Subsequently, Emma Frost had the surviving students engage in an free-for-all brawl, with those deemed to be the best performers assigned to a new team of trainee X-Men. Despite Frost's attempts to omit her, X-23 was among those students who made the grade.
Shortly afterward, following Stryker's attack on the depowered students, X-23 heard Dust talking to Icarus, who had fled the Mansion. Dust intended to meet Jay, but Laura told her it was a trap. She eventually had to knock out her roommate to keep her safe. Donning Dust's burka X-23 came to Stryker's compound and was shot. After a few minutes spent healing and playing possum, Laura returned to the Mansion to see it being attacked by Purifiers. Laura fought valiantly and helped fend off the intruders.
The kids grew to be more receptive of Laura following her part in stopping Stryker's attack, in which she single-handedly killed three Purifiers who had incapacitated Surge, Hellion, and Emma Frost. Subsequently, she started to bond with her friends, using her enhanced hearing to find out what happened to Icarus for them, learning that Stryker killed him.
After Surge received a distress call from Forge, X-23 followed the team to Dallas to rescue him from the sentinel Nimrod. At the height of the desperate battle she managed to cut through to the interior of the machine with her claws, allowing the sentinel to be defeated. She was mortally wounded during the battle by Nimrod's energy blasts and was unable to heal herself. In order to save X-23, Hellion supercharged his telekinetic powers in order to rush her back to the mansion where she was healed by Elixir.
As Hellion recovered his strength, and found that his power levels had been massively enhanced, Laura kept watch over him. Emma confronted Laura, asking her to leave the school because of the trigger scent. Their confrontation was cut short by Cessily coming to Laura's defense. Cessily pursued Laura, the two went out for coffee and discussed Laura's crush on Julian. However, the cafe was attacked by Kimura and her minions. It was discovered that the attackers have not come to reclaim Laura, but rather to capture Cessily.
Laura went back to the Xavier Institute; Hellion interrupted her as she was gearing up to attack against the facility. He informed her that he was coming with her. The two found a facility hideout where Laura interrogated a man at gun point. Upon securing the information she needed, X-23 shot him in the head. Julian was shocked and told her that killing would no longer be a part of their interrogation technique. X-23 looked at him, silently.
X-23 aided the X-Men in their fight against the Hulk. X-23 managed to knock over the Hulk and tore his eyes out. Eventually his eyes grew back, and he defeated X-23 by throwing her into a wall.
Following the birth of the first new mutant baby since M-Day, the New X-Men were not told because of the Purifiers involvement in the search for the child. Once they learned, Surge led a team to attack the Purifier base in Washington D.C., where they were ambushed by a new team of Reavers, wounding Hellion. Realizing they were out matched, Surge ordered X-23 to hold of the Purifiers while Pixie used a spell to teleport them. When the Sentinels were attacking the mansion, Iceman took the plane to bring the New X-men to safety. Laura jumped out of the plane and attacked the Sentinels. When Cyclops ordered Wolverine to assemble the new X-Force, X-23 was tossed into the mix. As they caught up to Cable, the Reavers attacked, and X-23 attacked Lady Deathstrike, apparently killing her. At Muir Island, X-Force attacked the Marauders and Predator X. When Predator X swallowed Logan X-23 became angry and attacked, and Wolverine finally killed it.
When the team, which also included Warpath, met for the first time in the field, Wolverine asked her to reconsider taking part in the operation, since he felt that she did not understand what she was giving up and stated that if she continued down this path she would not be Laura anymore, but X-23 once again. When Laura didn't step down, Wolverine conceded "Fine. Your life."
On their first mission, the team's investigated the theft of Bastion's cyborg head from a S.H.I.E.L.D. base. The trail led back to the Purifiers who had reactivated Bastion to help in their holy war against mutant-kind. During X-Force's raid on a Purifer base, and after killing many of its soldiers, Purifer leader Matthew Risman brought out a captive Wolfsbane, who had been caught earlier infiltrating the base and was now being held hostage at gunpoint. While Wolverine called for the team to stand down, X-23 decided Risman was bluffing and threatened him. Risman noted that X-23 has the "eyes of a killer", even more so than Wolverine as she was bred from birth to be a living weapon. After Wolverine commanded her to yield once again, X-23 appeared to surrender, but activated a concealed detonator that set off a series of powerful explosives she had planted earlier without telling her teammates. The explosion brought most of the base down around them but Risman was able to escape with Rahne during the chaos, despite X-23 leaving behind Wolverine and Warpath under rubble to pursue them.
When X-Force regrouped later, Wolverine admonished Laura for being so reckless with the lives of her teammates and for letting Rahne get kidnapped. Laura remorselessly replied to both accusations by coldly remarking "they survived" and "saving Wolfsbane was not my mission."
Later, when the team began to raid all known Purifier bases around the country in search of Rahne, killing and torturing many in the process, Warpath remarked that he couldn't see how Laura could be so indifferent to all the bloodshed they had caused, but Laura replied that she did not understand what he meant.
When X-Force retrieved Elixir so that he could heal Wolfsbane, Laura was not seen in the room, even though Warpath and Angel were. She approached Wolverine outside, who told her that he helped train Wolfsbane when she was a New Mutant. When Laura remarked that Rahne should have known better, she realized that her comment made Wolverine angry and he admonished her, telling her that Rahne was the person they should die for.
This confused Laura. She went into the forest alone and began mutilating herself with her claws. She caught the scent of Elixir's and Angel's blood respectively, and ran off to help them. She reached the room just in time to see Wolfsbane in her transitional wolf-form standing above Warren with his wings in her jaws. Laura prepared to attack Wolfsbane, but remembered what Wolverine said to her earlier about Wolfsbane being the one they should die for, and instead allowed Wolfsbane to slash her open.
Later, after she was healed by her healing factor, and Elixir healed both his and Angel's wounds, she discovered along with the rest of the X-Force that Angel's wings weren't organic, and that Elixir couldn't regrow them. She stood near Elixir while they both watched Wolverine and Warpath try to calm Angel down as he was suffering from seizures of pain. She informed everyone to look at Angel's back as "Something is happening." That something happened to be Angel transforming back into Archangel, who was watching X-Force and Elixir with malicious intent.
X-23 stayed by Elixir's side as they both watched Wolverine and Warpath attack Archangel and witnessed Archangel wound Wolverine. Laura was then wounded by Archangel. However, Josh healed her while Archangel attacked Warpath.
X-23, Wolverine, and Warpath followed Archangel in a jet, where she commented that Archangel's targets were moving. After the group managed to defeat (or rather delay) Bastion's evil plans, Archangel transformed back to his 'normal appearance'. The X-Men returned to Angel's home, where they attempted to understand what had happened to Wolfsbane and Angel, and also decided what to do with Elixir, who unfortunately knew too much about X-Force. X-23, believed the easiest thing to do would be to kill Josh, but she knew that would not be allowed. Instead, she went behind everyone's back and contacted the Stepford Cuckoos, who were loyal to Cyclops and would keep X-Force's existence a secret. X-23 and Josh requested that the Three-in-One erase Josh's memories of X-Force, thus allowing him to return home without being a risk to the team.
This didn't take place and X-Force was given a mission to capture the Vanisher and get back the Legacy Virus he managed to get. X-23 went with Archangel and Wolverine to complete the mission, but it ended in failure. X-23 also didn't trust Domino, even having her claws out when Domino was in the same room with her.
When the Vanisher came to Angel's mansion demanding to know what they had done to him, X-23 confronted him with the rest of the team. When Archangel said that clones "aren't real," X-23 didn't appear to care. She took part in retrieving the Legacy Virus that Vanisher left behind. X-23 also attacked the Marauders clones that attacked them, killing them with very little hesitation. X-23 then told Elixir not to "hold back" against the Marauders' clones. When X-23 tried to kill herself due to becoming infected with the Legacy Virus, Elixir stopped her and got rid of the Legacy Virus.
Messiah War X-23 later moved with the X-Men to San Francisco, where they were accepted as heroes by the mayor, having rejected the Fifty State Initiative. X-23 was roomed with Armor and Pixie. Laura left behind a towel covered with blood, which the latter brought to Emma Frost.X-23 was finally reunited with Kiden Nixon. Sadly this future version of Kiden was hooked up to several machines and was used as a generator in order to create a temporal anomaly that disrupted time travel technology, essentially trapping X-Force (which was lethal for them if they didn't return within 33.5 hours), Cable and Hope in that era. While X-23 agonized over killing Kiden or not (Kiden herself asked for death) the matter was taken out her hands when Domino shot and killed her. X-23, Domino and Proudstar were dispatched back in order to save Boom-Boom, however both Domino and Proudstar fell ill due to the time travel. Feeling grateful for saving her friend and ending her suffering, X-23 disabled the time travel devices on the other two and went back in time in order to save Boom-Boom herself. She arrived just in time to stop the Leper Queen before she could kill Boom Boom out of spite for X-Force not killing her. X-23 then collapsed in exhaustion. H.A.M.M.E.R. then stormed the building, giving medical care, while they took X-23 in for questioning.