The second injection came on the third day.
It wasn't targeted. The entire floor got it — what they called Fortification Testing, a phrase that meant nothing except that the mages moved through the cells in the afternoon with two handlers each and a new batch in the syringes. Pei Jin noticed the liquid as he queued. Not the usual turbid amber-brown. This was deep violet, viscous, the colour of wine left open too long in an iron vessel.
He felt nothing when it went in.
Three seconds later, the bones of his right leg began to burn.
Not the flesh — the bone itself. The marrow. The kind of burn you don't usually feel because you forget you have bones, until something presses a brand against the interior of them and holds it there. He said nothing. He walked back to his bunk, sat, pressed his palm against his thigh, and tracked the heat as it climbed.
When it reached his hip he understood this was not the usual.
He had watched 0736 die from a needle — first week, immediate convulsions, white at the mouth, gone before half an hour. He had also watched men spike a fever for three days and then return to baseline as if nothing had happened. The difference lay in the compound: some batches were standard diluted enhancer, others felt like concentrated toxin, stress-testing whatever floor the body would collapse through.
This was a third thing.
The heat climbed to his spine and then changed. On either side of his vertebrae something opened — not pain exactly, but the sensation of something being pulled apart to make room, a seam split lengthwise, and through that seam, something else was coming out.
He lay down on his side and faced the wall.
Whatever it was moved outward along his bones, all the way to his fingertips, which went numb — submerged-in-ice numb, then the feeling of something biting down and letting go. Then his head swam, briefly and hard, and then he came up the other side of it more awake than he'd been in weeks.
Sharper.
He could hear the man across the room breathing — shallow, ragged at the edge of each exhale. He could hear two mages talking outside the door at the corridor junction, discussing tonight's testing data. He heard the words interesting response before their voices rounded the corner. He could smell the rot in the straw piled in the far corner, the old iron smell of dried blood worked into the floor over months or years.
He had been able to sense all of this before. Not this clearly.
He lay still with his eyes shut and ran through what the mages had said. Interesting response — plural. He was not the only one. He needed to know who else.
He didn't sleep that night. He lay and felt the seam in him widening, felt the hollow along his spine grow, the way a cavity forms in cooling metal. The pain had passed. What remained was weight — a settled, downward heaviness, like ballast being added to the hull of something that had always been too light.
Before dawn he raised his left hand and held it against the dark above his face.
Beneath the skin of his knuckles, a thread of shadow moved. There and gone.
He put his hand down. He didn't think about it long. He thought about food.