The Nomu did not go down.
Its motion hitched. One beat. Less than a second. Then it resumed.
'Okay. So that didn't work.'
He'd expected that. The command was a test, not an attack. He was probing the architecture, trying to find a handhold in the forced reanimation. The dead tissue had heard him. The control layer had rejected it.
Two systems fighting over the same body. The flesh wanted to listen. The leash said no.
'Then I burn the leash.'
He let the Hound go. Not a hunt command. Containment. Circle and test. Find the seams.
The shadow came through the concrete at his feet. Just suddenly there. The temperature dropped.
The Nomu's hands came off Aizawa.
'Good. Look at me instead.'
The Hound struck the left knee joint. Necrotic cold spread through the dead muscle. Black crystalline ice. The Nomu's leg buckled.
Then the regeneration kicked in.
The frozen tissue thawed from the inside out. The external mechanism forcing the cells back online like someone rebooting a crashed system by hitting the power button.
The knee straightened.
'Are you serious right now.'
The Hound shifted targets. Knee. Shoulder. The stitched seam across the lower back. Hit and retreat. Hit and retreat. Every strike leaving frost that the regeneration had to burn energy to erase.
The Nomu swung and connected.
Izuku felt it in his chest. The connection between him and the Hound straining. Mana cost spiking hard enough to make his vision blur for a second.
'Three minutes at this rate. Maybe four. Then the Hound runs out of fuel and I'm standing in front of this thing with a gauntlet at 32% and my good looks.'
He watched the Nomu regenerate three strike points at once.
'Attrition's not gonna cut it. Not at range. The regeneration has a budget but I'll run out first.'
He looked at his right hand. Past the gauntlet. At the skin underneath.
The idea was simple. Terrible, but simple.
If he pushed the mana directly into the Nomu's body, skin to skin, the corrosion would hit the reanimation mechanism at the source. No surface freeze for the regeneration to patch. No hit-and-run. Just rot, at the foundation, from the inside.
The cost would be his arm.
He looked at Aizawa on the ground. Looked at the stairs where some of his classmates were still visible.
The cost would be his arm.
'Fuck it.'
He started walking.
***
Shigaraki saw him move.
"Nomu. Kill the kid first."
The Nomu turned. Covered ten meters in a single step.
The Hound intercepted. Full speed. Slammed into the creature's ribs and froze the entire left side of its torso.
One second of stumble.
Enough.
Izuku closed the distance. Put his right hand flat against the Nomu's chest.
And pushed everything he had through his palm.
***
The mana moved like floodwater through a cracked dam.
Through him. Out through his skin. Into the dead tissue.
He could feel the architecture of the thing laid out under his fingers. Every grafted quirk factor. Every stitched seam. Every point where dead matter had been told to move by someone who didn't give a shit what it had been before.
The necrotic mana spread through the Nomu's chest. Corroding. The command that said "move" being eaten by something that said "stop."
The regeneration fought back. The quirk factor surged. The skin at the contact point started cycling. Grey to black to grey to black. Rotting and rebuilding in a loop faster than his eyes could track.
The air turned white with frost.
His arm began to change color.
Grey. Starting at the fingertips. Creeping up through his knuckles. His wrist. His forearm. The veins darkening, black lines tracing the path the mana was taking on its way out of his body.
It hurt.
Not sharp. Not hot. Something deeper. The structural ache of a body being used as a conduit for something it was never meant to carry. His bones were conducting necrotic energy. His muscle fibers were acting as a wire between his chest and the Nomu's dead flesh.
The wire was burning.
'Thirty seconds. Maybe forty before this arm stops working permanently.'
He pushed harder.
The Nomu screamed. The noise of meat vibrating at a frequency that shouldn't exist. Every person in the plaza who still had functioning ears flinched.
The regeneration was losing. The Nomu's movements went erratic. One arm twitching. A leg buckling, straightening, buckling again. The targeting script fragmenting.
Shigaraki was screaming something from the water's edge. Izuku couldn't hear him over the sound of his own blood in his ears.
His arm was grey to the elbow.
He couldn't feel his fingers.
'Ten more seconds. Give it ten more seconds.'
The Nomu's chest caved. The tissue at the contact point simply stopped being held together. The mechanism failing completely. A hole opened in its torso. Black. Crystalline. Smoking.
The creature staggered backward.
Izuku's hand came free. Grey. Dead-looking. Fingers curled inward in a way he hadn't told them to.
The Nomu was still standing. The hole was already trying to close. New tissue forming at the edges. Ugly. Slow.
But slow. The foundation was compromised.
'That's all I had.'
The Hound was gone. Dissolved on its own. Fuel spent.
His knees buckled. He caught himself with his good hand. Stayed on all fours for a second, breathing hard, vision going grey at the edges.
'Get up. Get up, you idiot, it's still—'
The ceiling exploded.
***
All Might came through the dome like the concept of violence had decided to arrive in person.
No pose. No grin. No catchphrase. Just a man with his fist already drawn back and a look on his face that Izuku had never seen in any episode, any panel, any poster. The face of someone who was done performing.
He hit the Nomu in the compromised zone.
The shock absorption engaged. But the tissue at the strike point had nothing left to absorb with. The mechanism was gone. The regeneration was running on fumes. All Might's fist went through.
The second punch came before the first finished resolving. Then the third. Then the fourth. Each one landing in the rotted core, the place where Izuku's mana had eaten the foundation out from under everything.
The Nomu left the ground.
Went through the ceiling the way a bullet goes through paper.
Then it was quiet.
***
Izuku was on his knees.
Right arm hanging. Grey from fingertip to elbow. Veins dark. Fingers still curled in a fist he couldn't open. The mana reserve was empty. Not low. Empty. The cold in his chest was gone. The shadow at his feet was just a shadow.
The silence was the worst part. For months he'd had the constant background hum of the Hound's stored presence. The tax on every breath. The second heartbeat.
It was gone. The quiet was deafening.
All Might landed beside him. Steam coming off his shoulders. Breathing hard. The labored breathing of a body running past its limits.
He looked at the boy's arm. The grey skin. The black veins. The clean line at the elbow where the color stopped.
He looked at the black crystalline residue evaporating from the concrete. The same substance he'd found in an underpass months ago.
"What are you?"
Quiet. The voice underneath the posters.
Izuku looked up at him. Eyes flat. Exhausted. The green in them almost grey.
He didn't answer. Didn't have the energy to answer. Didn't have the energy to lie.
Shigaraki's voice cut from the water's edge. Thin. Breaking.
"Cheating — this is cheating — Sensei SAID—"
Kurogiri's portal opened behind him.
"We're leaving, Tomura Shigaraki."
The mist swallowed them.
The plaza was empty.
Sirens outside the dome. Getting closer. The sound of a world about to start asking questions.
Izuku looked at his grey arm. Tried to move his fingers.
They didn't move.
'Well. That's a problem.'
He almost laughed. Almost. The same kind of laugh he'd had in the alley behind his apartment ten months ago, standing in the rain with splinters in his hair. The laugh that comes when the situation is so profoundly, catastrophically stupid that crying would be giving it too much credit.
His arm didn't work. His mana was empty. His shadow was just a shadow.
And he was kneeling on broken concrete in a destroyed training facility next to the Symbol of Peace, who was looking at him like he was a question that might not have an answer.
'This is fine. Everything is fine.'
His vision went grey.
Then black.
TO BE CONTINUED