Survival.
It was not a complicated word. It did not require extensive unpacking or philosophical elaboration. It was, in fact, one of the most functionally precise words in any language Elias had encountered across the three he currently had access to, and he had encountered many languages in fifty-four years of existing in a world that rewarded precision above almost everything else.
Survival. The continuation of biological function against adverse conditions. The base requirement beneath every other requirement. The variable without which all other variables became irrelevant.
For seven days it had been the first thought that arrived when he woke and the last thought present when he slept, which was itself a change from his previous life, where the first and last thought had reliably been whatever problem he was currently mid-solution on. He had not decided to make survival his primary cognitive thread. It had simply installed itself there with the quiet authority of something that understood its own importance.
This world, as Jonas's memories and one week of direct observation had confirmed, was not a safe one.
That was perhaps an understatement.
In the German Empire, in the year that Elias was increasingly certain corresponded to somewhere in the fourteenth century of this world's history, the basic volatility of daily existence was a fact so thoroughly accepted that most people had stopped noticing it, the way a person stops noticing the smell of a room they have lived in long enough. A mage of sufficient rank could ruin a man's livelihood over a perceived slight and face no meaningful consequence. A dispute between two noble houses could result in a village that had nothing to do with either house being reduced to ash because it happened to sit on contested land. Economies lurched and destabilized around the supply of magic stones — dense, crystalline formations that stored Flux with a consistency and concentration that organic matter could not maintain, making them simultaneously a power source for enchanted weapons, a raw material for the alchemical inks used to inscribe magical instruments, an ingredient in potions that allowed mages to supplement depleted reserves, and consequently the single most fought-over commodity in the known world.
The price of magic stones moved markets. The control of magic stone deposits moved armies. Being in the wrong place when two parties wanted the same deposit could end a life with the same casual indifference as weather.
Elias had noted all of this with the systematic attention he applied to everything, and reached the same conclusion on day two that he suspected any rational person would reach on day two, if they were the kind of person who was honest with themselves about their situation.
He was a fifty-four-year-old scientist inhabiting the body of a malnourished fourteen-year-old minor noble's third son in one of the most politically volatile regions of a world run entirely by people who could throw fire with their hands.
He had no magic. He had an ability that no one in this world had a category for and that he himself did not yet fully understand. He had knowledge that no one else in this world possessed and that would get him killed if the wrong people discovered it before he was in a position to manage that discovery.
What he did not have was time to be comfortable.
The ability, at least, was developing into something he could begin to map.
Over the seven days he had run what tests the limited conditions of a medieval castle bedchamber permitted, working in the pre-dawn hours when the household was quiet and the risk of interruption minimal. What he had established was this: the anomaly — he had stopped calling it that internally, because anomaly implied something temporary, something that might resolve back into normalcy, and nothing about his situation suggested normalcy was an available destination — the ability responded to energy of multiple types. Thermal, as the candle had demonstrated on the first morning. Kinetic, as a stone dropped from waist height and stopped mid-fall on the third morning had demonstrated, though the precision of that particular test had been approximate at best. Cold — the absence of thermal energy — which he had discovered on the fourth morning when the overnight frost on the window shutter had retreated from his hand faster than any body heat alone could account for. And magic, which he had not yet been able to test directly but which the theoretical framework demanded should behave consistently with the other energy types.
He could absorb. He could redirect. He could, and this had been the most interesting discovery of the week, apply the stored energy inward — to the body itself. On the fifth morning he had redirected a quantity of absorbed thermal energy into his right hand, and the hand had been noticeably warmer for the following three hours. The hand had also been steadier. Stronger. He had gripped the edge of the writing desk and left a mark in the wood that had not been there before, which was not nothing for a malnourished adolescent with underdeveloped musculature.
He had sat and thought about this for a long time.
There had been a series of illustrated novels — comics, they were called, the vintage physical print editions — that Greta had kept in an organized collection in the house they had grown up in. She had tried repeatedly to get him interested in them as a child. He had resisted on the grounds that fiction was not an efficient use of reading time, which he recognized in retrospect as exactly the kind of thing a very unpleasant child would say. He had eventually read several of them in his late thirties during a period of insomnia, partly out of guilt and partly because they were available and his own materials were in the laboratory. He remembered, with the clarity that attached itself to information he had not expected to find interesting, a particular category of character. Beings from another world — a planet with a different sun — whose biology, when exposed to the radiation of Earth's yellow star, became something beyond what their original physiology suggested. Stronger. Faster. Nearly indestructible. Capable of things that their home world's physics would never have allowed.
He was not making a direct equivalence. He was not, despite what his second wife had occasionally implied, prone to magical thinking or wishful extrapolation from insufficient data.
But the structural parallel was not nothing.
An organism from one dimensional reality, now embedded in a different one, exposed to an ambient energy field that organism's original dimension did not possess, developing a capacity to interact with that field in ways the native population could not. The physics was not the same. The mechanism was not the same. But the basic shape of the situation had a family resemblance to something he had read in Greta's living room at three in the morning while waiting for his brain to stop running calculations long enough to permit sleep.
The potential was, he concluded, significant. Very significant. The kind of significant that required careful management and extensive preparation before it could be responsibly explored, because the other thing he had established with certainty in seven days of observation was that his current body was nowhere near capable of handling what the ability might eventually be asked to do.
He had absorbed a quantity of redirected thermal energy on day six that had seemed, by his best estimate, modest. The body had disagreed. His hands had shaken for two hours afterward. He had been useless for the remainder of the morning, which was not a condition he intended to repeat. He had not experienced what he could confidently identify as backlash — the energy had dispersed without apparent structural damage — but the body's reaction had been clear enough that he did not require backlash to understand the message.
The vessel was fragile. And a fragile vessel, loaded with more than it could structurally bear, did not survive the experiment.
This was not a problem unique to this world or this situation. It was an engineering problem, and engineering problems had engineering solutions. The solution, in this case, was the same solution it had always been throughout human history when the available tool was insufficient for the required task.
You improved the tool.
He had, in his previous life, completed the mandatory five years of military service that the Swiss Confederation still required of its citizens in 2247, albeit in a modified civilian-researcher capacity that the military had instituted for personnel whose theoretical value exceeded their practical combat utility. He had not been a soldier in any meaningful combat sense. What he had been was a weapons developer embedded with active training units, because you could not design equipment specifically calibrated to the physiological and tactical requirements of elite soldiers without understanding elite soldiers at close range, and you could not understand elite soldiers at close range without being around them while they were being elite soldiers.
He had held two masters degrees and a doctorate by the time he completed that service. He had also, by the time he completed it, a very thorough empirical understanding of what a body trained to genuine military standard was capable of, because he had watched that standard being built and maintained at extremely close proximity for five years while simultaneously designing the tools those bodies would carry into the field.
He was under no illusions about what he currently had access to. Jonas's body was fourteen years old, significantly underdeveloped for that age, and had not engaged in any meaningful physical activity in at least two years, as evidenced by the practice sword in the corner that had accumulated dust undisturbed long enough to suggest it had been abandoned rather than merely set aside.
He was also under no illusions about the direction that needed to change.
On the morning of the eighth day, Elias picked up the practice sword.
It was a simple thing — a wooden training blade, blunted, weighted approximately correctly for the age it had been made for, which meant it was lighter than he would eventually need and heavier than Jonas's current arm strength found comfortable. He held it, adjusted his grip twice, noted the body's residual muscle memory from the two years of practice that had preceded the abandonment, and began to move through the most basic forms that the memory contained.
The forms were not good. They had not been good when Jonas practiced them and they were worse now, because two years of disuse had degraded whatever modest competence the boy had been building and Elias was working from Jonas's muscle memory rather than his own, which meant the motion felt simultaneously familiar and incorrect, like reading a translation of a text he had originally encountered in a different language. The general shape was present. The precision was not.
He noted this without frustration, because frustration was not a productive response to accurate assessment, and accurate assessment was that the forms were bad and that bad forms practiced repeatedly without correction became bad forms with better endurance, which was not an improvement worth having.
He would need instruction eventually. For now he had the memory, the sword, and the dawn, and that was enough to begin.
He practiced for an hour. The body objected, mildly, in the particular way of underused musculature being asked to perform after an extended period of rest. He noted the objection, catalogued which specific muscle groups were generating it, and continued until the hour was complete. Then he put the sword back, cleaned up any evidence of exertion that might be visible, and went down to the morning meal.
He was aware of the whispers before the end of the first day.
Castles were not, he had quickly established, environments that accommodated privacy in any meaningful sense. They were large, stone-built, acoustically peculiar structures populated by people with limited external stimulation and considerable professional investment in knowing what everyone around them was doing. The servants talked. The serving staff talked to the kitchen staff who talked to the stable hands who talked to the guards, and the guards talked to each other, and all of them, eventually, talked to anyone who asked.
Jonas von Stein, the inert third son, the quiet disappointment, the boy who had not touched his practice sword in two years, was apparently getting up before dawn and practicing again.
Elias was aware of the whispers and found them, on balance, acceptable. He could not have concealed the practice entirely without confining himself to his room, which would have generated its own set of questions and accomplished nothing toward the actual goal. What he could do was ensure that the practice looked, to anyone who might observe it, like exactly what it appeared to be: a boy who had quietly decided to take his training more seriously. Unremarkable. Slightly surprising, given the two-year gap, but not alarming. Not threatening. Not the kind of thing that would cause anyone to look closely at the reasoning behind it.
Let them whisper. Whispers were preferable to scrutiny.
He kept his expression, in all other interactions, precisely as it had been in the first week — quiet, attentive, slightly absent, the look of a boy whose thoughts were somewhere else. Jonas had worn that expression so consistently for so long that it had become the face people expected when they looked at him. Elias found it extraordinarily useful. The people who expected to see nothing of consequence when they looked at you were, in his experience, the easiest people to stand directly in front of.
He had one week of data and a body that was already, marginally, less fragile than it had been on day one.
It was not enough. It was, however, a beginning, and Elias Cord had learned thirty years ago that the only meaningful difference between a beginning and a solution was the number of steps between them and the willingness to take each one in the correct order.
He picked up the prayer book that night, opened it to the page of ongoing observations, and added a single line beneath the previous entry.
Day eight. Physical conditioning initiated. Ability parameters continue to expand. Threat assessment: significant and ongoing. Response: preparation, patience, and the understanding that this world does not yet know what it is dealing with.
He closed the book.
Outside the warped shutter the Bavarian night was cold and entirely indifferent to the plans of the small pale boy sitting at the writing desk inside it.
He found this, as he found most things that were indifferent to him, an acceptable condition to work within.
He blew out the candle and went to sleep.