The reindeer gave itself up slowly, the way good things tend to.
The first indication was on the second day after eating, when he picked up a rock near the river that he had previously been using as a seat and realized he was holding it at chest height before his body had registered the effort. He set it down and looked at his hands and picked it up again. The rock weighed what it had always weighed. His arms just didn't care about that the way they used to.
He went back for the rest of the reindeer the same day.
The remaining leg he had left wrapped in leaves was still good, the cool forest air and the tight vine binding having preserved it well enough. He picked it up with one hand, the whole thing, and carried it back to the cave without a drag line, and the thirty minute walk was the same thirty minutes it had always been except that his shoulder was the only thing complaining and it was complaining less than it had been.
He ate methodically over the following days. Not with the desperate animalism of the first meal but with the focused intention of someone conducting an experiment they were invested in. He cooked portions, ate them, waited, assessed. Each time the shaking came it was shorter and milder, his body processing the input with increasing efficiency, and each time he came out the other side he was incrementally more than he had been.
The strength was not superhero strength. He was clear eyed about this in the way that managing expectations prevents disappointment. He could not lift a tree. He could not punch through stone. What he could do was lift things that a strong man might lift, the upper range of human physical capability, the kind of strength that wins competitions in the world he had come from and causes people to stop and look twice. He was dense with it, low and solid, his center of gravity dropped in a way that made him feel rooted when he stood still, hard to move, hard to shift, like the reindeer's massive stable body had donated something of its architecture to his.
He found this out by running into a tree deliberately at increasing speeds until the data was sufficient.
The tree lost more of the exchange than he did.
The weeks accumulated.
He started with the trees near the cave, jumping to the lowest branches, pulling himself up with the right arm and then both once the shoulder permitted it, moving along the branch to the trunk and up to the next level. His legs made the initial jump easy and getting easier, the height he could clear from a standing position increasing in increments that still surprised him when he stopped to measure them against the trunks. He found he could reach branches that were four meters up from a standing jump, five if he pushed properly, and the landing absorbed cleanly through his legs without the jarring impact that physics suggested it should produce.
He started moving between trees. Not climbing down and up, but crossing the gaps between canopies where the branches grew close enough, pulling himself hand over hand, dropping and catching, building a route through the forest above the ground that he came to know as well as the paths below. He fell twice in the first week. Both times he landed and the landing was acceptable and he climbed back up and continued.
His radius expanded daily.
He set a rough measure of a kilometer as his increment, pushing further each day, mapping what was out there. The forest continued to be vast and old and largely indifferent to his presence. He found more evidence of the creatures he had already encountered, rabbit tracks near water, reindeer grazing areas in the wider spaces between trees. He found things he hadn't seen before, prints in soft ground that suggested something large and heavy moving on four legs, claw marks high on tree trunks from something that climbed.
He catalogued and kept moving.
Four weeks after the reindeer his body had returned to itself and then exceeded it. The tracksuit was a problem now in ways it hadn't been before, the shoulders and chest of the top pulling against muscle mass that hadn't been there when he had bought it. He had let it out where he could, cutting the seams and relacing them with vine, a modification that looked exactly as practical and as terrible as it sounds. He had stopped caring about how he looked approximately three weeks before he had the thought to care about it.
He was investigating a track set he didn't recognize when he found them.
The prints were small, four-legged, the toes spread in a way he hadn't catalogued yet. He was crouched over them following the line of travel, the bone spear across his knees, when the light changed on the ground ahead of him.
Not the light from the canopy. Something closer.
He looked up.
There were three of them, maybe four meters ahead, sitting in a cluster on the dark earth between two roots. Blue-green, translucent, roughly the size of large dogs but with the structural confidence of things that knew they didn't need conventional anatomy to be dangerous. They moved with the slow pulsing motion of something that operated on its own timetable, their surfaces catching the filtered canopy light and bending it in ways that made them look like they were lit from inside.
Slimes.
Actual, genuine, unambiguous slimes.
He stayed absolutely still in his crouch and looked at them and felt something he hadn't felt since the first day he had arrived here, genuine uncomplicated excitement, the kind that sits in the chest and makes thinking difficult.
Slimes had magic. This was not an assumption he was making based on nothing. This was accumulated knowledge from a significant personal library of fantasy novels and manga consumed over years of evenings and commutes, a library that had turned out to be the most practically applicable education he had received in his entire life. Slimes dissolved things. Slimes had elemental affinities. Slimes in the stories were either the weakest possible enemy or secretly the most broken entity in the setting depending on which story you were reading and he was aware that this forest had already demonstrated a preference for the second category.
He looked at them moving slowly between the roots.
He looked at his spear.
He looked at the slimes again.
The question of how exactly one killed a slime with a bone spear was one he did not have a confident answer to. Stabbing a gelatinous entity of indeterminate internal structure with a pointed stick felt like an approach with obvious limitations. He needed to think about this. He needed to think about what slimes were vulnerable to, what slimes did when threatened, what the practical reality of fighting something with no skeleton and no obvious vital points actually looked like when you were the one holding the weapon.
He needed to not get dissolved.
He stayed in his crouch and watched them and the excitement in his chest did not diminish because whatever the answers to those questions were he was going to find them, because those slimes were sitting between him and an ability set that the words did not currently exist to describe and he had not come this far, had not dragged himself bleeding through this forest for weeks, had not eaten a horned rabbit and a reindeer and built weapons from rocks and leaves and vine, to stop now because the next step looked complicated.
He shifted his weight slightly and one of the slimes pulsed and turned toward him.
Its surface caught the light and bent it blue-green and he could see through it to the earth and roots behind it.
He tightened his grip on the spear.
"Okay," he said quietly, to himself, to the slimes, to the forest and its general policy of providing him with problems and no instructions.
He started thinking.