"'Who are you' is one of those questions that's always tricky to answer," she responds. She makes herself a chair and sits. "I think perhaps hearing my story chronologically is the best answer to those questions."
"I was born in a world with no magic, no essence, and no non-human sapients. The world was a sphere of rock spinning through space, warmed from within by rocks still glowing and liquid from its formation, warmed from without by the light of a giant burning ball of gas that was its sun. We had plants, animals, mountains, sand, and many things that seem at least somewhat similar to here. It was ... okay. We had environmental problems too, actually, but they hadn't reached the same dire point they had here. And there were other problems -- wars, death, food insecurity, petty tyranny."
"And so I grew up and dreamed of a better future, and worked to help in ways that I could, but never really accomplished much. Until one day, I figured out how to build a machine that perfectly and completely controls the location of things within a given radius. It took me years to scrape together a prototype -- it filled a whole room of my house, and had to be powered off of an external generator to avoid browning out the neighborhood -- but it let me assemble extremely accurate parts, which let me assemble more miniaturized (and precise) components, which compounded, until I was able to create this."
She summons a pale purple fixity crystal and floats it above her hand.
"I call it fixity crystal. It does the same thing my initial machine did -- let you control the location of things within a given radius -- but it's self-contained and self-sustaining, needing no external power."
"Once I had this, I knew I had what it would take to fix my world's problems. Controlling location also lets you turn things into other things, for example. The way that I make water is by taking the tiny constituents that make up the air, and rearranging them into the pattern for water. And this would eventually let me give people everything that they needed -- food, land, healing -- without needing to deplete any external resource."
"So I used my initial flakes of fixity crystal to build larger fixity crystal, and so on. I moved to the center of the ocean, to be sure that I could do so uninterrupted. I also shared the news with everyone, and talked about how it should work when I eventually had a large enough crystal. Eventually, I did. I built a crystal that covered the whole world, and used it to provide people with what they needed. I made some mistakes, at first. I think with the wisdom of hindsight I could do better a second time. But I solved the problems that had bothered me as a child, and ushered my people into an era of plenty."
"With time and plenty to spare, we turned our attention to the stars. We established cities on the moon, and built castles that soared high above the surface of the world, beyond the air. We were reaching out to build homes around our closest star -- we would have gotten there in another 10 years or so -- when I was suddenly visited by a traveler from another world."
She takes a sip of water.
"She took the form of a notebook, and said that she was a messenger from the Spirit of Femininity Unleashed. She offered me powers unlike any I could replicate myself. Instead of running on understanding the smallest forms and patterns of the universe, they run on stories. And they let me do things I had only dreamed of. It's one of her powers that lets me have multiple bodies in different places while still remaining one person."
"And although she couldn't give me the power to travel between worlds directly, she could send me to another world, possibly one where I could learn to travel further on my own. One where I could help another world in dire need. One where my story could continue."
"So here I am! In a world of strange magics unlike anything I have ever known, with some powers forged by my own hand and some powers granted to me by a being beyond my comprehension, trying to leverage both to help people who desperately need it."
"You asked who I am: I am the small child who saw her world was unacceptable. I am the lucky scientist who found a way to fix it. I am the passionate dreamer who wanted to build a paradise in the stars. I am the fortunate woman who caught the eye of something greater. And I am the person who chose to step away from all that to become someone else's traveler from beyond, not knowing how or when I may return."
And then, because Amethyst has specific habits built up by a lifetime of not being able to tell when her explanations have hit the mark, she asks "Did that answer your question? I got a bit poetic. I should probably give a more concrete description as well."