Samantha's past was more or less like what you'd expect any normal child to experience. Though she never knew who her mother was, she had a father that looked after her and helped her grow to become a respectful person. Indeed, if her life stayed that way she would still be leading a normal life.
The start of it all
When Samantha turned eleven, her innate powers were revealed. This all came about from research taking place at the Steelhead base in canada into combating the psychic soldiers that VIPER was producing. The plan, however, was not to stoop to the same level as the villainous organisation but to find people within their own ranks that possessed psychic abilities. Everyone and their families were screened, as long as they were willing, but anyone that was directly part of the project was just told it was a medical test. only a handful of people proved to have even a hint of ability and Samantha was one of these people, since her father was a key researcher for the project.
When it was discovered though, her father was very insistent to not use her further for the project. At first they agreed and Samantha went on living normally, but as the other participants proved to have nothing useful they could expand upon, there was more pressure to let her go for further testing. Eventually, after all the other participants failed, Samantha's father had no choice but to let her go through the tests.
Much to the dismay of her father, Samantha proved to be the only successful one of the group of participants and she was finally let in on what was going on and why she was going through all these tests.
The turning point
At the age of twelve, Samantha had become pretty well integrated into the project. She helped the researchers by acting as subject for a prototype suit that would enhance psychic abilities, namely those of a telekinetic nature. She was given an advanced education compared to what she would have gotten in a normal school, and it showed as she occasionally gave her own suggestions into the making of the suit. Though this probably came more from her having first hand experience in what she was doing to make it work than from the extra education alone.
Still, her father wouldn't let her be anymore than a subject for the prototype. Eventually the suit would be advanced enough to unlock the telekinetic abilities of even normal foot soldiers, and Samantha could go on to living normally. It was an agreement Samantha was happy with too, since she didn't see herself as a fighter but was still glad to help out as she could.
Unfortunately, VIPER caught wind of the project and had been doing some spying on the whole thing. They had found out who the key researchers were and knew about Samantha and the suit. During another day of testing, VIPER secretly attacked the base with their assassins, stealing all data about the suit and destroying the data saved in the base. They also killed many of the researchers, but when they went to the last objective of their mission, they met a big hitch.
While the suit was being tested by Samantha and other researchers, including her dad, the VIPER assassins’ attacked. They were precise and quick, and before anyone even knew what was going on, Samantha's dad and a couple other researchers were already dead. It took a few seconds to sink in, but when Samantha realised what had happened, her reaction was all but instant. With the suit already active, she blasted the assassins into the wall with a furious telekinetic push that knocked them all out. Samantha wasn't content to stop there though and was clearly going to end her father's killers, but one of the engineers for her suit shut it off before she did something she'd regret. Moments later, the assassins were arrested and dealt the proper justice.
Although it was quick and the memory fuzzy to her even now, the event changed Samantha's opinion on her role in the project. She now wanted to help in the fight against VIPER when she could. Though it was against her father's wish for her, she would eventually become the hero she is today.
Three years after the invasion of the project and the death of many of the researchers, the Psychic Enhancement Suit (P.E.S.) was finally ready for field testing. With only the engineers of the suit having survived, the making of the suit was much slower than anticipated and the resources afforded to the project became ever smaller to the point those involved had to work on it in their free time, and take the P.E.S. off site. Essentially it became more of a home project than a military project. Thankfully it also meant VIPER never caught on to the fact that the suit was still being made. Samantha and the small team of four that stayed with the project even as it died in the eyes of their superiors, worked on the P.E.S. tirelessly. Samantha herself also took lessons in self defence and learned other advanced ways of fighting. Her physique meant she was average in all this, but it meant she had a basis she could use for when fighting with the P.E.S.
The P.E.S. was also specially designed for Samantha, as it was impossible to work on a mass producible version with the limited resources for the project. This meant it was able to tap into her abilities completely, letting her form shields, weapons, cages and ranged bursts of energy.
With the suit now ready, Samantha and the small team that finished the P.E.S. were ready to reveal their creation to the world. And it couldn't have been at a better opportunity, as they got to prove that all their hard work was worth it when Samantha helped fight off the Qularr during the Millennium City invasion. From that point on, Samantha's career as a hero started, and she would be sent to help keep the people safe from danger. And although VIPER was at the top of her list of things to fight, Samantha learned to put protecting people first and her vendetta second.
Who is Mental Block?
Samantha is generally a quiet and thoughtful person. Her experiences have made her able to take things much more seriously than a normal child, and she often solves things in a mature fashion. That said though, she can occasionally be very normal and child like, especially when faced with new or emotional situations, or even when she just lets herself be relaxed.
Samantha has innate telekinetic abilities, but is unable to use them without the Psychic Enhancement Suit. No matter how hard she focuses she wouldn't even be able to push a feather with her mind without the suit. She does have self defence knowledge though, so she's not completely helpless without the suit.
When she is wearing the P.E.S. Samantha has access to a whole slew of abilities which mostly focus on the creation and manipulation of telekinetic matter. She can create various kinds of blade (sometimes two if she focuses hard enough) as well as personal shields which supplement the energy shield built into her suit for when she can't focus enough or if she needs to block a more focused hit. She can also create telekinetic bubbles that protect friends or trap enemies and can also send out damaging blasts of energy that may even send her foes flying. Alternatively she can focus her energies around herself to make herself fly.
Since her powers rely on the P.E.S. Samantha can be left very vulnerable if it gets damaged. If it gets damaged to the point of being unusable, she'll even lose her ability to escape.
Another aspect Samantha has to be careful of is focus. If she loses focus at a key moment, she could leave herself open for attack. Thankfully her suit's shield doesn't need much focus to be used, so she can activate it when she needs to retreat and get her head together.
The last notable weakness Samantha has is the fact that she is still a child despite the way she tries to act. When faced with a new or 'scary' situation she can sometimes cower away. But also, she can get very protective of friends and family, and may jump into foolhardy situations to help them.