X-2: Demonic Blades
The second of the 14 was originally Hadrianna Parks, a Faunus employee of a private security firm, and an individual with a colorful past. She was a former member of the White Fang, an advisor to the Menagerie chapter leaders Corsac and Fennec Albain. However, one of the members was a little too possessive of her, which resulted in an incident where she was supposedly sexually abused by the member. When she approached the brothers about it, they simply dismissed it on the grounds of "having other important matters to attend to" and she received no assistance. Fed up with the lack of responsibility that the brothers ignored, she departed from the White Fang and began a campaign to expose acts such as what happened to her.
Her big mouth eventually got her into trouble, and was targeted by the very man who abused her after he was discharged from the White Fang under orders from Sienna Khan. He raped her and left her for dead, having broken both of her arms and in a ditch. She was found by an Alliance field operative, who nursed her back to health and recruited her into the program. She underwent surgery to receive new weapons, which came in the form of new, robotic arms that carried a set of twin blades that could extend from her arms. She underwent vigorous therapy to help her adjust to the arms, as well as training in the use of the blades.
Due to her former career as a Private Security officer, she was adjusted to the violence of combat when she experienced her first deployment in the field. She took part in Operation: Spearhead, an Alliance operation to slow the rapid growth of the White Fang Splinter Cell that was under Adam Taurus' command. She swiftly assassinated several of the violent radicals who had called themselves White Fang, showing slight remorse towards the action. This was understandable, as any life taken when there could have been a chance at redemption deserves to be mourned. Afterwards, she resolved to rescue all of the Faunus from Adam's lunacy and spiteful nature and even became a mentor to X-1.
The next of the 14 is such a troublesome duo, so I am uniting X-3 and X-4 into their own chapter.