BIOGRAPHY - Page 4
Along the way, Piotr tried to teach Sarah more about true beauty, for example by enjoying landscapes or the pictures in an art exhibition. Among the paintings was even one of his own, depicting his little sister, Illyana. Most of the time, Marrow used an image inducer to hide her bone horns, but at one point she decided to pull them in, like Xavier had been trying to teach her. She succeeded and managed to keep them in for a half a day, until she lost concentration when a young man started flirting with her. Colossus had no idea she wasn’t using the inducer, and was rather proud of her having made such progress. Without warning, the pair were suddenly transported to the Hill, by Mikhail Rasputin, who offered to 
resurrect Illyana with his reality shaping powers. While Colossus fought his brother over this insane plan, Marrow was left to confront her own memories regarding her upbringing on the Hill. She realized how much she had changed since then, both in appearance and attitude. She turned on her former Morlock leader and sided with Colossus. Together, they were able to free Mikhail of some evil entity’s influence he was under, and returned to Xavier’s mansion in Westchester with him. [Uncanny X-Men (1st series) #373-374]
In fact, all of the X-Men had returned to the Institute, because of the apparent death of Wolverine. However, it turned out that it was just a Skrull imposter, him having been the traitor that Xavier had sensed earlier. More shocking, however, was the discovery that the true Wolverine had been brainwashed into Apocalypse’s new Horsemen - Death. It took the combined effort of the X-Men and many of their allies and former members to free Logan and stop Apocalypse’s plan to take over the world. [Uncanny X-Men (1st series) #375, X-Men (2nd series) #95, The Twelve crossover]
Still recovering from this adventure, the X-Men already faced another crisis, as the High Evolutionary had created a device to deactivate mutant genes on a global scale. Like every other mutant, Sarah lost her powers and looked fully human. 
Unsure what to do, Storm convinced Marrow to come with her to Camp America, as a mentor for underprivileged children. Although unwilling at first, she tagged along and eventually began to enjoy her time there, even dating a boy named Brad. About a week later, some of the other X-Men had pinpointed the High Evolutionary’s orbital base and devised a plan to deactivate his machine. Sarah actually didn’t want to give up her happiness, but she understood that it was for the greater good and joined the team in invading the base and destroying the Evolutionary’s device. [Uncanny X-Men (1st series) #379, X-Men (2nd series) #99, Uncanny X-Men (1st series) #380]
Although the specific circumstances have yet to be revealed, a few months later, Marrow‘s bone growth went of control again and she left the X-Men for good. [X-Men Revolution Six-Month Gap]
[Note: A popular theory is that Marrow found out about Gambit’s involvement in the Mutant Massacre, turning her life upside down. However, it could also be merely the case that because of the High Evolutionary’s manipulations of the mutant genome, her uncontrolled bone growth kicked back in.]
At some point, SHIELD operatives found Marrow disoriented and confused in the sewers and brought her in. Using drugs and brain conditioning, they turned her into an assassin of rogue LMDs (Life Model Decoys). Marrow was implanted with a false memory of a being a young woman named Sarah Rushman, this persona being used to keep her under control during the day, 
while at night she would go hunting for her targets. In her human guise, Sarah started flirting with Peter Parker (who believed his wife, Mary Jane, to be dead), and they eventually went out for coffee. During the date, Sarah was attacked by SHIELD agents, because she had missed the last doses of her drug and had become unstable – her condition being not unlike a multiple personality disorder. While fighting, Sarah changed into Marrow and ran away but, as his alter ego, Spider-Man, Peter followed her and tried to appeal to her sense of good. However, having been manipulated and used against her will, Sarah wouldn’t want to hear any of it and jumped off the Brooklyn Bridge, letting both SHIELD and Spider-Man think her dead. Secretly, though, she made her way back to the Morlock tunnels, where she was welcomed by her former teammate, Hemingway, of Gene Nation. [Spider-Man/Marrow One-Shot]
Marrow kept a low profile for a while, until she received word of someone able to provide her with her greatest desire - a flawless appearance. In return for her becoming an agent of the revamped Weapon X program, the project’s scientists promised to do their best to restore her good looks. Although painful, the experiment succeeded, as all Sarah’s excessive bones were cast out of her body, 
killing some of the lab staff in the process. Despite her looking entirely human now, she could still create bones weapons when needed. To prove herself, marrow was given her first assignment - to kill D'Gard, the current leader of Gene Nation and, as such, a former teammate and friend. Before completing this mission, however, she took a detour to a club, reveling in her new appearance and the attention it brought; she even had sex with a handsome young man. The entire time, though, she was being observed by operatives of the Weapon X program. In fact, the handsome man turned out to be none other than fellow agent Mesmero, who had fooled Sarah with his hypnotic powers. Emotionally destroyed, Marrow vowed never to allow anyone to be close to her again and committed herself to her old ways. She killed D’Gard as requested and was fully added to the ranks of Weapon X’s super-powered operatives, though not before giving Mesmero a decent beating. [Weapon X - The Draft: Marrow]
How much Weapon X’s upgrade had improved Marrow’s abilities became clear during her first few assignments; like when she formed a blow gun and a dart out of bones to kill the president of a South American country during a soccer game, for example. [Weapon X (2nd series) #2]
Marrow was among the first to notice that not all operatives were loyal to the Weapon X project's director, Malcolm Colcord, because his second in command, Brent Jackson, was scheming behind his back and luring more and more agents to his side. However, not being entirely devoted to the program either, Marrow didn't mind Brent Jackson inviting her to join his subgroup as well, her actually playing on both sides of the fence and trying to make the best of it, no matter which of them would gain the upper hand. [Weapon X (2nd series) #4, 9]
Because of his involvement in the Mutant Massacre back in the day, Marrow had a hatred for her fellow agent, Sabretooth, and eagerly accepted the task of tracking him down when he defected from the Weapon X program. Director Colcord personally handpicked her for this assignment, well aware of her desire for revenge, and even allowed her to use lethal force, if there was no other way. When she finally found Creed, it was in the strangest of places - in the sewer system underneath the Weapon X program's headquarters. In this confined space, she confronted Sabretooth, confessing that she used to be afraid of him but that she had overcome her fear. At first, Creed laughed at her but, when she popper bone claws similar to Wolverine's, Marrow finally got Creed's full attention. During their fight, Marrow
surprised Sabretooth more than once with the bone structures she could create, though sooner or later he would have overpowered her. Apparently realizing this herself, Marrow opened a flood valve and, while she used her extra bones to hold herself in place, Sabretooth was hurled through the sewer system, out of the mountainside that the base was built upon. Although the fall was surely being not enough to kill Sabretooth, Marrow felt that she had at least made him pay somewhat for the Morlocks' death. [Weapon X (2nd series) #10, 12]
When Marrow returned to the Weapon X compound, she found it under siege by Jackson, his lackeys and their latest set of allies - Cable's underground movement. However, as soon that it was clear that had defeated Colcord's loyal agents and chased them out of the base, Jackson betrayed Cable's team, luring them into a trap. Following their being captured, Jackson ordered them to be mindwiped and brainwashed, in which Marrow saw her perfect chance to pursue her own agenda. She freed Cable's team and escaped with them, only to feed them further lies about what had happened, in order for Cable to give her a disk, containing all the contact information of the various Underground cells he had founded all over the world. [Weapon X (2nd series) #13]
With Cable believing to have won his war against the Weapon X program and as such no longer needing his Underground movement, Marrow could easily take over the network and turn them into a new and much more powerful Gene Nation. Naturally, her defection from the Weapon X program came with a price, as she found herself slowly reverting to her old looks. However, by then, Sarah found her beauty a small sacrifice to make for the "greater good." In the name of mutant superiority, Marrow had her followers perform several successful and well-placed terrorist attacks, quite many of them on Weapon X related facilities. 
Not willing to let themselves be further humiliated by one of their defected operatives, the program sent their most deadly operative, Agent Zero, formerly known as Maverick, after her. He got rather mad when he learned that Marrow had even lured a former sidekick of his to their side, Zero being forced to kill him in order to prevent Grand Central Station being blown up, or so he believed. Actually, his former sidekick had only pretended to go along with Marrow's plans, trying to stop her organization from within. Marrow's action having caused him to kill his own friend, Zero got even by killing Marrow's personal bodyguards, including Hemingway. In their final confrontation, Marrow told Zero that she was ready to die for what she believed in, but Agent Zero decided against killing her, as that would have turned her into a martyr. Instead, he humiliated her by hunting down and killing each and every single member of Gene Nation, making sure that she had no more followers to boss around. He even promised to return when she would least expect it, and finish the job he had started. [Weapon X (2nd series) #19-21]