Betsy Button

The mutant at the center of the De-Aging Epidemic of 2019 and 2020.

Early Life
Despite Betsy's earliest memories taking place during wartime, her early life was relatively uneventful. She has vague memories of growing up as the youngest looking student in all her classes. Her mother called it aging gracefully, but both parents did find it suspicious when their daughter was seemingly still just entering puberty a few years into high school.

It was when she was twenty-six that it became clear to Betsy what was going on with her. She was at an anti-war protest and someone displeased with the stance her and her friends took assaulted them. Her friends were dead, but Betsy was left unharmed, looking like she was fresh out of high school again.

The 70s through the 2010s
Betsy lived recklessly over the years, realizing she could take chances without suffering repercussions. She did not use this to amass wealth or gain notoriety; she saw how people reacted to those different than her. She saw that fear in humans, particularly the ones older than her and recognized that she was going to be there to replace them one day. That was why humanity feared her and feared mutants.

Captivity
In 2017, after SUPER relocated some operations into the MROverse, some agents tracked down evidence of Betsy and her mutation. With effort, they were able to restrain and bring her into an off-site research facility. This team began experiments centered around Betsy's genetics, conducting experiments on her and using her blood and tissue.

When SUPER was separated from the AV and the organization started moving in a new direction, the black site research facility severed communication with SUPER, working independently on their genetic research. Using Betsy as their primary point of research, they developed a synthetic serum meant to de-age human, mutant, and even adapted cells, modeled using Betsy's X-Gene without incorporating the X-Gene itself as an ingredient.

Escape
The trigger for Betsy's de-aging was not clear, but the poking and prodding was causing micro-adjustments to her age. When she was left alone with a particularly vicious researcher, she antagonized him until he struck her. When he struck several times, frustrated, she was able to revert in age enough where her wrists and hands were small enough to escape her restraints. She used one of the serum syringes on the captive and watched him revert back to childhood. Recognizing her opportunity, she made off with as much of the serum as she could manage in liquid and gas forms.

The De-Aging Epidemic
Targeting mutants, Betsy utilized her serum in an effort to "gift" youth to mutants. Recognizing that the Echo Beta Serum did not depower mutation strength, she determined that giving mutants time at an earlier age to develop their powers even further would accelerate their ability to phase out older generations of humans and claim the world for themselves.

Mutation
Reactive De-Aging: When Betsy endures harm, her body responds by de-aging her physically, healing the damage in the process. The amount her body de-ages scales with the degree of harm she experiences.


 * Toxin Immunity: Toxins, drugs, and even alcohol do not affect Betsy, as their effects are recognized as harm by her body and will trigger the de-aging process to clear the toxins.
 * Incapacitation Immunity: While Betsy can experience normal sleep, she cannot be knocked unconscious, as this would be prevented when the damage inflicted is healed away by de-aging.
 * Mental Retention: Unlike Serum victims, Betsy's de-aging does not revert her mind, allowing her to retain memories and knowledge normally, even as her body de-ages.