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Regulus Black had not entered the cave expecting mercy.
He had not entered it expecting rescue, redemption, forgiveness, or any soft, shining miracle from the dark. He had come because he had seen, with the cold clarity of a boy raised on ancient names and poisoned pride, that some things could only be answered with sacrifice. Not victory. Not glory. Sacrifice.
He had come because the locket had to be taken.
He had come because Kreacher had been ordered to obey him.
He had come because the Dark Lord had made one mistake.
He had trusted that Regulus Black was only a spare.
Only the younger son. Only the quiet one. Only the shadow beneath Sirius’s burning star. Only a Black boy with polished manners, a perfect posture, a name old enough to bruise, and a devotion so deep it had rotted him from the inside out before he’d even understood what devotion meant.
The cave breathed around him.
Cold, wet stone. Black water. A ceiling high and jagged as the inside of some ancient beast’s ribs. The lake lay still beneath the greenish light, too smooth to be natural, too silent to be empty. The island at its centre was small and cruel, nothing but stone and the basin and the terrible potion that had already hollowed him out.
Regulus knelt beside the basin, shaking so hard his bones felt loose inside his skin.
The potion burned in him.
It had not been pain in any simple sense. Pain was clean. Pain had shape. Pain could be bitten down on, endured, hated. This had been invasion. It had crawled through his veins and peeled him open thought by thought, memory by memory, dragging every weakness to the surface and holding it under the light.
Mother’s voice, sharp as silver.
Father’s silence.
Sirius leaving.
Sirius surviving.
The Dark Lord’s approval.
The Dark Lord’s contempt.
The endless, gnawing knowledge that Regulus had been born second and had spent his entire life trying to make second mean worthy.
He had drunk until there was nothing left in the basin.
He had screamed. He knew he had. The sound still trembled somewhere in the cave, caught in the stone like a trapped animal.
Now his throat was raw. His lips were wet. His face was slick with tears and lake water and something that felt like fever. His fingers, cramped and shaking, closed around the real locket.
The Horcrux.
Small. Gold. Heavy with murder.
Kreacher stood beside him, wringing his thin hands, eyes enormous and shining with panic.
“Master Regulus,” Kreacher whispered. “Master must give Kreacher the locket. Master ordered Kreacher to take it. Master said Kreacher must destroy it.”
Regulus tried to answer.
His tongue felt too large. His mouth tasted of metal and grief. His thoughts scattered like startled birds.
The locket pulsed in his hand.
Once.
Softly.
Like a heart.
Regulus sucked in a breath so sharp it hurt his ribs.
“Kreacher,” he rasped.
The lake moved.
At first, it was only a ripple.
Then another.
Then the water broke.
White hands rose from the black surface.
Kreacher shrieked.
Regulus turned his head slowly, vision swimming, and watched the dead climb out of the lake.
Inferi.
Bodies bloated and pale, eyes blank, mouths hanging open as water streamed from them. Fingers hooked over the stone. Knees dragged. Nails scraped. They came from every side, lifting themselves out of the lake with a horrible patience, surrounding the island in a closing ring of dead flesh and wet bone.
Kreacher leapt toward Regulus.
“Master! Master must give Kreacher—”
The cave shuddered.
A crack split through the ceiling.
Regulus looked up.
Stone groaned overhead, deep and furious, as if the cave itself had finally realised theft had occurred inside it. Dust rained down. Pebbles struck the island. The green light trembled. The water churned black around them.
“Kreacher!” Regulus choked.
A boulder tore loose from the ceiling and smashed into the lake, sending up a wave that slapped hard over the island. Kreacher was thrown backward with a cry, arms flailing, his small body skidding across slick stone.
The inferi surged.
Regulus clutched the locket to his chest.
“No,” he breathed, though he did not know whether he spoke to the dead, to the cave, to Kreacher, or to himself. “No—”
Kreacher crawled toward him.
“Master Regulus! Kreacher comes! Kreacher will—”
Another violent tremor ripped through the cavern.
The stone beneath them split.
Kreacher was hurled away again, thrown toward the edge of the island by the force of collapsing magic and falling rock. He vanished for a breath behind the spray of black water.
Regulus tried to stand.
His legs buckled.
The inferi reached him.
Cold hands seized his robes. Fingers dug into his arms, his shoulders, his throat. Regulus snarled, panic flashing through the potion-haze, and thrashed like an animal. He kicked, elbowed, clawed at them, but there were too many. Wet hands dragged at him. One locked around his wrist. Another tangled in his hair.
The locket burned against his palm.
Kreacher screamed his name.
Regulus could not see him.
The cave was falling apart.
Stone crashed into water. Dust filled the air. The green light flickered and warped, stretching the shadows of the inferi long and monstrous across the island. Everything was noise: the cave collapsing, the dead crawling, Kreacher sobbing, Regulus’s own ragged breathing.
He was going to die here.
That had been the plan.
That had always been the plan.
But the locket was still in his hand.
His sacrifice had failed.
Something inside him snapped.
Not cleanly. Not like a thread. Like an old door kicked open from the inside.
Magic burst out of him.
It came without wand, without word, without thought. Instinctual. Ancient. Furious.
The air cracked.
The nearest inferi were blasted backward into the lake, limbs twisting, mouths open in silent screams they did not have the life to make. Black water rose in a violent ring around the island. The cave walls flashed with silver-white force.
Regulus gasped.
His eyes flew wide.
The magic did not stop.
It poured out of him, raw and wild, crawling beneath his skin like lightning searching for roots. His blood answered it. Old blood. Black blood. Generational magic, deep and dark and sleeping in the bones of his line, magic older than the house tapestry, older than its curses, older than the proud carved motto that had hung over his childhood like a sentence.
Toujours pur.
Always pure.
Always waiting.
A rock fell.
Regulus turned too late.
It slammed down against him, striking shoulder, chest, arm. Pain exploded through him. He hit the stone hard, the breath knocked from his lungs. The locket was crushed between his body and the jagged edge of fallen rock.
Gold cracked.
A thin, ugly sound.
The locket split.
Not fully. Not cleanly.
Partly.
Enough.
Blackness spilled from it.
Not smoke. Not shadow. Something thicker. Something alive.
It slid over Regulus’s fingers before he could release it, sinking into his skin as if his flesh were only water. He screamed.
Kreacher, still sprawled near the island’s edge, froze.
“Master?”
Regulus writhed beneath the fallen stone, clutching the broken locket to himself. His back arched. His fingers dug into the gold. The dark magic seeped deeper, threading through veins, nerves, bone, thought. It did not simply enter him. It recognised him.
A Horcrux, cracked and hungry.
A soul-fragment, furious and clever.
An ancient bloodline, dark and proud.
Prodigy.
Genius.
Ambition.
Devotion.
Insecurity.
The spare. The second son. The boy who wanted to matter so badly he had let a monster make him useful.
The broken thing inside the locket fed on all of it.
Regulus’s scream broke into a laugh.
It was not loud at first.
It came out ragged, breathless, almost confused.
Then it sharpened.
The inferi stopped moving.
Every one of them.
Around the island, across the water, half-risen from the lake, crawling over the stone, they halted as if some invisible leash had snapped tight around their throats.
Regulus went still.
Kreacher’s ears flattened.
The cave continued to crumble, but more slowly now, as though the very stones had begun to hesitate.
Regulus’s hand tightened around the broken locket.
His breathing steadied.
His head lowered.
Then, very slowly, he pushed himself up.
The fallen stone should have kept him pinned. It did not. It shifted as his magic gathered under it, grinding aside inch by inch until Regulus could drag himself free. His robes were torn. His shoulder was bleeding. His face was pale as death.
But his eyes—
Kreacher whimpered.
His eyes had changed.
The grey was still there, but not as it had been. It had deepened, darkened, silver swallowed by something green-black and burning. The veins at his throat and wrists showed through his skin in thin, shadowed lines, not blue but dark, branching like ink beneath porcelain. His mouth, once trembling from potion and pain, curved with slow, poisonous amusement.
The locket hung broken in his grip.
The cave was silent enough to hear water drip.
Regulus looked down at the inferi nearest his feet.
Its blank eyes stared up at him.
He tilted his head.
“Kneel.”
The inferius obeyed.
So did the others.
One by one, around the island, the dead sank down. Some folded awkwardly. Some bowed until their foreheads touched stone. Some lowered themselves into the water and floated there, submissive, waiting.
Kreacher stared.
Regulus’s smile widened.
“Well,” he murmured, voice hoarse and velvet-dark, “that is new.”
Kreacher crawled closer on shaking limbs.
“Master Regulus?” he whispered.
Regulus did not look at him immediately. He looked at the inferi, his expression sharpening into something assessing, something lordlike, something that wore command the way his family wore heirlooms.
Then he glanced down at Kreacher.
The house-elf flinched, though he did not move away.
Regulus’s gaze dragged over him, cold and glittering.
“Kreacher,” he said softly.
“Yes, Master Regulus.”
“You were going to leave me.”
Kreacher recoiled as if struck.
“No! No, Master, Kreacher would never—Kreacher was pushed, Master, the cave was breaking, Kreacher could not reach—”
Regulus stepped toward him.
The inferi shifted with him.
All of them.
Kreacher’s breath hitched.
Regulus noticed.
A pleased look crossed his face.
“Do not lie,” he said. “Not to me.”
“Kreacher is not lying, Master,” Kreacher sobbed. “Kreacher lives to serve Master Regulus. Kreacher would die for Master Regulus.”
Regulus stared at him.
For a moment, something flickered behind his eyes.
Not softness.
Memory, perhaps.
Then it was gone.
He lifted the broken locket.
The cracked gold gleamed wetly in the cave’s sick light.
“I came here willing to die,” Regulus said. His voice echoed differently now, ringing off stone as if the cave itself wanted to carry it. “I came here believing death would make me useful.”
Kreacher pressed his forehead to the stone.
“Master is useful. Master is great. Master is brave.”
“Brave,” Regulus repeated, and laughed under his breath. “Bravery is what people call stupidity after it produces results.”
The inferi remained bowed.
Regulus moved among them slowly, boots clicking over wet stone. His limp should have been worse. The rock had struck him hard. He should have been shaking. He should have been weak from the potion, the blood loss, the collapse.
Instead his magic poured around him in a black, rippling aura, invisible until it touched the water and made it draw back.
He stopped before the nearest kneeling corpse and looked down at it with open contempt.
“I never thought inferi essential,” he said, as if continuing a conversation only he could hear. “They’re crude and unspeakably plain.”
Kreacher lifted his head slightly, confused.
Regulus’s smile sharpened.
“But maybe they’ve a glimmer of potential,” he continued, eyes sweeping across the gathered dead, “if allied to my vision and brain.”
The inferi did not react.
Their dead faces remained slack.
Regulus sneered.
“Yes,” he murmured. “That will be a problem.”
He turned toward them fully, robes dragging through shallow water and blood. His wand lay somewhere on the stone, forgotten. He did not need it. Not now. Power coiled in his fingers, under his tongue, behind his teeth.
“I know that your powers of retention are as wet as a warthog’s backside,” Regulus said, voice growing stronger, crueler. “But thick as you are, pay attention. My words are a matter of pride.”
Kreacher stared at him with wide, shining eyes.
The inferi stayed bowed.
Regulus lifted one hand.
A dozen dead heads snapped up at once.
Kreacher gasped.
Regulus’s expression warmed with satisfaction.
“There,” he said. “Better.”
A tremor moved through the cave again, but this time Regulus merely glanced upward, annoyed, as if the collapse were an inconvenience and nothing more. The crack in the ceiling stopped spreading.
Kreacher trembled harder.
“Master Regulus has powerful magic,” he whispered. “Master Regulus has magic like old Blacks.”
Regulus looked at him.
“Old Blacks,” he echoed.
The phrase sank into him like wine.
His family had always told him blood mattered. Blood remembered. Blood carried duty, greatness, shame. They had poured that belief into him from infancy, and he had swallowed it because children swallowed what they were given.
Now his blood did remember.
It remembered darkness.
It remembered command.
It remembered kingship.
Regulus drew in a slow breath.
The broken locket pulsed against his palm, but no longer as a separate thing. Its rhythm had slipped into his. His own heartbeat answered it. His thoughts moved faster now, sharper, bright and merciless. The cave, the inferi, Kreacher, the locket, the Dark Lord, Dumbledore, Sirius, the whole miserable structure of the world—it all arranged itself before him like pieces on a board.
He had been sent to kneel.
He had been expected to serve.
He had been expected to die quietly and make someone else’s story cleaner.
No.
Regulus Black straightened.
“It’s clear from your vacant expressions,” he told the inferi, pacing before them, “the lights are not all on upstairs.”
Kreacher made a distressed noise.
Regulus ignored him.
“But we’re talking kings and successions,” he continued, his smile curling. “Even you can’t be caught unaware.”
The inferi watched him.
Blank.
Obedient.
His.
The word slid through him with exquisite pleasure.
His.
Regulus turned sharply.
The nearest inferius rose without being ordered aloud, reacting to the flick of his fingers. It stood dripping and silent, waiting.
Kreacher covered his mouth.
Regulus’s eyes flashed.
“So prepare for a chance of a lifetime,” he said softly. “Be prepared for sensational news.”
His voice dropped into something intimate, almost reverent.
“A shining new era is tiptoeing nearer.”
The cave seemed to lean around him.
Kreacher shook his head, baffled and frightened and loyal all at once.
“Master’s era?”
Regulus looked down at him.
“And where do you feature?” he asked, each word light as a knife laid flat against skin. “Just listen to teacher.”
Kreacher swallowed.
“Yes, Master.”
Regulus crouched before him.
The motion was elegant despite the blood, despite the ruin of his robes. He reached out and touched Kreacher’s chin with two fingers, lifting the elf’s face. Kreacher trembled under the contact.
“I know it sounds sordid,” Regulus said, “but you’ll be rewarded.”
Kreacher’s eyes filled with tears.
“Rewarded?”
Regulus smiled at him.
“When at last I am given my dues,” he said, “and injustice deliciously squared.”
The word injustice tasted sweet.
It should not have.
It did.
Every slight sharpened inside him. Every time Sirius had been louder, brighter, freer. Every time Walburga’s approval had landed on him like a chain instead of a blessing. Every time the Dark Lord had looked through him, measuring usefulness and nothing more. Every time Dumbledore had watched from his castle and moved children like shields on a board. Every old wizard. Every old name. Every person who had expected Regulus Black to die in the dark and be useful for it.
His jaw tightened.
“Be prepared.”
Kreacher bowed again.
The inferi bowed with him.
Regulus rose.
The movement rippled through the dead like a command. They waited. Hundreds of them beneath the water. He could feel them now. Not as bodies. As extensions. Cold points of obedience in the lake. A kingdom of drowned things.
The locket throbbed.
The cave no longer felt like a tomb.
It felt like a throne room.
Regulus stepped to the edge of the island and looked over the black water.
“For the death of the Dark Lord,” he said.
Kreacher froze.
The inferi did not.
Regulus glanced back, amused by Kreacher’s terror.
“What?” he asked. “Did you think I would crawl back to him?”
Kreacher’s mouth opened and closed.
“Master Regulus was loyal,” he whispered.
Regulus’s eyes went hard.
“I was devoted,” he said. “There is a difference.”
The cave hissed with dripping water.
Regulus looked again at the lake.
“We’re gonna kill him and Dumbledore too.”
Kreacher made a strangled sound.
“Master—”
“Do not,” Regulus snapped.
Kreacher flung himself flat.
“Forgive Kreacher.”
Regulus stared down at him, upper lip curling. The anger in him flared hot and immediate, but it did not scatter him. It focused him. He liked that. The potion had dragged him apart; the locket had put him back together wrong, and stronger.
“There will be a king,” Regulus said.
The inferi stirred.
Regulus lifted his chin.
“I will be king.”
The lake answered.
Dead hands rose from the water, not attacking now, but reaching upward like worshippers.
Kreacher sobbed quietly against the stone.
Regulus looked almost bored by it.
“Stick with me and you’ll never go hungry again,” he said, with a faint sneer of amusement, as if the promise itself entertained him.
Kreacher peeked up.
“Master will let Kreacher stay?”
Regulus’s gaze slid to him.
“Kreacher belongs to me,” he said simply.
The elf shuddered.
“Yes,” Kreacher whispered. “Kreacher belongs to Master Regulus.”
Regulus smiled.
“Long live the king.”
The words fell into the cave.
The inferi bowed lower.
Kreacher repeated it, voice thin and trembling.
“Long live the king.”
Regulus’s smile became something terrible.
The broken locket had fused deeper now. He could feel it beneath his sternum, behind his eyes, threaded through thought and instinct. It whispered, but not in another voice. That was the worst part. The best part.
It sounded like him.
It sounded like every thought he had never dared to finish.
Why serve what you can surpass?
Why die for a master who would not know your grave?
Why be the spare when the world can be made to kneel?
Regulus spread his fingers.
The inferi rose.
Hundreds of dead bodies shifted in the lake and on the island. Pale faces turned toward him. Water streamed down their ruined robes. They stood in uneven ranks, grotesque and silent, but the sight of them did not disgust him anymore.
It delighted him.
He looked them over, his expression calculating.
“It’s great that you’ll soon be connected,” he told them, “with a king who’ll be all-time adored.”
Kreacher, still kneeling, stared between Regulus and the dead.
Regulus began to pace again, the ruined hem of his robes whispering over stone.
“Of course, quid pro quo, you’re expected,” he continued, “to take certain duties on board.”
One inferius tilted its head as if listening.
Regulus laughed softly.
“Good.”
A chunk of stone fell somewhere behind him, crashing into the water. The inferi did not turn. Kreacher flinched. Regulus did not.
“The future is littered with prizes,” he said, eyes bright, “and though I’m the main addressee…”
He paused beside Kreacher, looking down at him.
“The point that I must emphasize is,” Regulus said, slow and clear, “you won’t get a sniff without me.”
Kreacher nodded frantically.
“Kreacher understands. Kreacher needs Master. Kreacher follows Master.”
“As you should.”
Regulus turned back to the dead.
“So prepare for the coup of the century,” he said, lifting his broken locket hand.
A wave rose behind him, black and obedient.
“Be prepared for the murkiest scam.”
The inferi shifted as one.
Regulus felt them respond to the rhythm of his will. Each corpse was a thread. Each thread was cold and dull, but strong enough when gathered. He could pull them. Send them. Stop them. Make them kneel. Make them kill.
His blood sang.
The locket burned.
His veins darkened further, shadows crawling beneath the skin of his hands. His reflection flickered in the water: pale face, dark eyes, cruel mouth, something regal and ruined staring back from the black surface.
He liked it.
He looked like what he had always been told his name should mean.
He looked like a Black.
“Meticulous planning,” he said, almost lovingly.
His mind moved ahead at once. Plans branched and sharpened. The Dark Lord’s immortality. The locket’s broken remains. The cave. Kreacher. The inferi. The magic now waking in him like a beast uncaged.
“Tenacity spanning,” he continued.
He thought of years spent trying to earn notice. Years of silence. Years of obedience. Years of being formed into a weapon for someone else’s hand.
His smile faded into something colder.
“Decades of denial,” Regulus said, “is simply why I’ll…”
He stopped.
The cave waited.
Kreacher barely breathed.
Regulus’s gaze lifted, and in that moment he was not the shaking boy who had drunk poison. He was not the spare. Not the terrified son. Not the Death Eater realising too late that the god he had followed was only a butcher with better theatre.
He was something else.
Something newly born in the collapsing dark.
“Be king undisputed,” Regulus said.
The inferi bowed.
“Respected, saluted.”
Kreacher pressed his forehead to the stone again.
“And seen for the wonder I am.”
His voice carried through the cavern, smooth and bitter and full of heat.
“Yes,” he said, smiling with all his teeth, “my teeth and ambitions are bared.”
The dead opened their mouths.
Regulus lifted his hand.
“Be prepared.”
Kreacher whispered it first.
“Be prepared.”
Then the inferi answered—not with voices, not truly, but with the scrape of bodies shifting, the wet pull of limbs through water, the collective motion of obedience.
Regulus laughed.
The sound echoed up into the broken ceiling.
He looked down at Kreacher.
“Say it properly.”
Kreacher trembled.
“Yes, Master.” His voice cracked. “Yes, our teeth and ambitions are bared.”
Regulus’s smile returned, pleased and dark.
The inferi shifted around them, and the cave seemed to breathe in.
Kreacher bowed so low his ears touched the stone.
“Be prepared.”
Regulus stood at the edge of the island with the broken locket fused to his hand, the dead waiting at his command, the cave bowing around him, and the last fragile pieces of the boy who had come there to die sinking beneath black water.
He did not mourn them.
He had been weak when he entered.
Devoted.
Useful.
Expendable.
Now the poison had stripped him bare, the stone had broken the locket, and the thing inside it had found fertile ground in all the old rot his family had planted.
Regulus Black breathed in.
The cave smelled of lake water, death, dust, and power.
Kreacher stayed kneeling.
The inferi stayed waiting.
Regulus looked out over his drowned army, eyes shining darkly, and clutched the shattered gold against his chest.
The spare was gone.
Something crowned in shadow had taken his place.