For most, 'the beginning' starts with one's mother and father. Their childhood and what their life was like. Happy, sad, broken or whole. Family is the cornerstone to one's upbringing. But Cassandra doesn't have that. Her birth was part of a plan. Her genetics carefully chosen. She was born and placed into the hands of master assassin David Cain. She was the latest in a succession of children from which he was attempting to mold the perfect successor from and it didn't take long for him to realize that Cassandra was something special. She had a gift, a potential that only needed honing. Shaping. And he endeavored to be that shaper. He taught her in every known deadly weapon, common or exotic, simple and high-tech. And he taught her how to fight in close-quarters combat with nothing but your own body to rely on. He raised her devoid of speech, so that combat would be her only language, to give her the edge that would make her surpass him. To make her worthy to be the heir to the legacy of Cain. Just as David Cain is the 'God-chosen Killer', so did he name her Cassandra, for her almost precognitive knowledge of what her opponent would do and beat them to the strike.
He succeeded. Cassandra was the perfect killing machine, a living weapon with no morals or preconceptions of how life 'should' be imposed upon her from the outside world. Everything she knew was the bunker that Cain raised her in, and what he told her to do. In its way, it was a simple life. Cain devoted all of his energy and time to her, and despite the oddity of their relationship to an outsider who might balk at his teaching methods, such as shooting her to provide motivation, she was happy. She knew nothing else. And then he had her perform her first hit.
Nine years old, dressed in a cute pink dress, she made her way to her target. He and his guards simply smiled and laughed, never suspecting that the cute child before them was a trained killer. With her little had she tore out his throat and only then, in his dying moments, did she realize what she had done. She had hurt men before, left them broken and battered and bleeding, but never had she killed before. Looked into the awful face of death and known herself to be the cause of that terror, seen the light go out behind his eyes. She ran then, away from the father that she loved, the life she knew. She drifted from city to city, never staying in one place too long, getting by from day to day by begging, stealing, or scavenging for her needs. And eventually, her wandering brought her to Gotham.
Cassandra Cain was bred to be one thing. The best assassin on the planet. David Cain chose her mother with care and raised her with that singular goal in mind. To that end he taught her everything he knew. About fighting. About weapons. And he was not alone. The League of Assassins were also her trainers, each contributing to the vast pool of her combat knowledge. She knows the human body intimately. How it works. How to hurt it. How to kill it. If someone had to pick one word for her? Perfect.
While Batgirl relies heavily on her ability to read her opponents, her skills go beyond that, zen-like. It comes from the higher levels of training in martial arts where you open yourself up to feeling the hostile intent of someone and knows that you should move. This sense is so highly tuned that it allows her to dodge bullets that she doesn't know are coming at her. In a straight fight, she's almost unhittable.
Part and parcel of being an assassin is being able to go unseen and when Cassandra dosen't want to be, she isn't. She knows how to use shadows and misdirection and staying just outside of someone's viewplane. Even against normally alert individuals such as police and guards she can get right up behind them without them being any the wiser. After all, those are the kinds of people an assassin needs to be able to avoid.
Unlike, well, just about everyone, Cassandra has the ability to give everything the equivalent of her full attention at the same time. Things that take intense concentration and focus comes second-nature to her. This makes her aggregate speed on par with meta-humans and, shy of running blood tests, is often assumed to be so. She is the pinnacle of human physical output. All she lacks is the knowledge and experience to use that to greatest effectiveness. Even lacking that, she's damned impressive.
Getting in and out unseen and leaving bodies in your wake. Cassandra can lift ID cards, pick locks and know how to kill a man without just about anything. Especially herself. She has a very in-depth knowledge in a rather specialized field.
Cassandra's first language is violence. Deprived of words in any form during her formative years and instead trained nearly every waking hour to be David Cain's successor, she learned to interpret meaning out of movement. In combat this makes her seem almost precognitive, but it also allows her to know when someone is lying and in some ways what they're thinking.
Given that movement is her language, it's not surprising that she has a natural talent for dance but no formal training.
When you get hurt a lot, you learn first aid or you don't live that long. While nothing fancy, Cassandra can bandage herself or others up and otherwise take care of them until help arrives.
Despite her still somewhat limited ability to converse with others, Cassandra is actually very bright and a fast learner especially in matters of physical activity. She is able to watch someone's body language and copy it almost perfectly as well as adapt it to herself. Every day with Cain was learning something new. A new style of Martial Art, a new weapon, how to disassemble or reassemble firearms. She enjoys learning and the look of satisfaction on her teachers faces when she is able to exceed their expectations. Because of the way Cassandra reads the movements of others, which borders on living the moment herself, she is able to learn such things as combat or dancing, movement-skills, in minutes and hours rather than days, months, or years. She doesn't even need someone to take her hand and teach her, and can learn just by watching someone actively engaged in the activity.
As part of her training, Cassandra was taught to ignore pain. She still feels it, but she doesn't let it stop her. It hardly seems to slow her down. It's to the point that she can keep herself from what most would assume to be instinctive, automatic reactions. Like flinching when she's shot.
Cassandra has been living alone, on the streets since she was nine years old, drifting from city to city across the globe. She knows the types of places you can find food and and where to find shelter both urban and rural. You could drop her in the middle of pretty much anywhere and while it may not be pretty she'll do one thing. Survive.
This date is significant as the night she made her first and only kill and it haunts her to this day. It is what drove her to leave everything she knew and loved, to that discovery that life is a precious thing that must be protected at all costs. It is why she'll sacrifice her life if need be, to save others. Especially on this night she will drive herself to extremes to try and keep it free of shadow of death.
In a fight, she's perfect. She bases her life around that fact. Even when she wasn't, losing isn't really an option to her. Even if it would be smarter to just let it lie, stand there, or walk away, she can't. She has to prove that she's the better. Faster, tougher, stronger, she wants those around her to *know* that she's better than they are. Perhaps because she is so lacking in other things. Winning proves the point that she's not incomplete. Not less a person than they. Too bad it's herself she needs to convince of that.
The demon on her back. It rides her. The death of a man that she didn't even know. Blood on her hands. Something that she can never give back. Can never make right. And so she'll put herself in harm's way. Again and again. To save others and maybe, one day, she'll find peace.
Cassandra's brain just doesn't work the same as other people's. Her language centers are all over both hemispheres of her brain and so learning to read, write and speak like most people is exceptionally difficult for her. She only knows a handful of words and can't read or write at all. She even has trouble identifying individual letters.
Every night, she re-lives that awful moment when she tore out a man's throat. When his life's blood spilled out over her hands and the light went out behind his eyes. She lives with the guilt, the horror, the fear, of knowing that she is capable of taking a life. They wake her up in a cold sweat, and never allow her to move past that moment. To forget or have any measure of peace. Re-lived every night, the images haunt her during her waking hours, and she has no love for sleep, knowing that it is to this she will return.
Having never gone to any formal schooling, Cassandra lacks knowledge that many of us take for granted. Sure, she knows a lot, she's bright, and makes well-informed decisions. But she doesn't know the multiplication table, nor what a noun or verb is. She doesn't know who the presidents of the United States were, that there ever was a Cold War, or that plants need water and sunlight to grow and thrive. So many things that those who have gone to school take for granted she has never known, and doesn't realize that she is missing them.
Cassandra has enemies. Those that want to use and control her. Some, she doesn't even know about. Cain. Shiva. The League of Assassins.