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The castle was quiet in the particular way Hogwarts only ever was on late spring evenings.
Not silent—never silent. Hogwarts breathed. It hummed. Stone corridors carried distant laughter, the echo of footsteps, the occasional slamming door three floors away.
But the seventh–year Gryffindors had found a stretch of corridor that felt almost peaceful.
The windows overlooking the grounds glowed gold with the setting sun. Warm light spilled across the flagstones, painting the corridor in amber.
And sprawled across the floor in various states of laziness were the Gryffindor seventh–years.
Sirius Black leaned against the wall, long legs stretched out, lazily flicking a chocolate frog wrapper at James Potter’s head.
James dodged it without looking.
“Your aim’s getting worse, Black.”
“My aim is flawless,” Sirius said lazily. “You’re just annoyingly quick.”
Remus Lupin sat cross–legged with a book balanced on his knee, though he hadn’t turned a page in fifteen minutes. He was listening to the chaos instead.
Peter Pettigrew was half–lying against Gideon Prewett’s shoulder while Gideon and Fabian argued about whether they could successfully charm the suits of armour to start dancing during dinner.
Mary Macdonald sat with Marlene McKinnon and Lily Evans near the window ledge.
Alice Fortescue leaned against Frank Longbottom, who had an arm draped loosely around her shoulders.
It was the comfortable sprawl of people who had known each other for seven years.
Relaxed.
Content.
Nearly done with Hogwarts.
James yawned. “I vote we go down to the lake.”
“Seconded,” Fabian said immediately.
“Thirded,” Gideon added.
Lily snorted. “That’s not a thing.”
“It is if we make it one.”
Sirius pushed himself off the wall.
“Come on then,” he said. “Before Moony starts forcing us to revise.”
Remus didn’t even look up.
“You all failed the last Defence essay.”
There was a collective groan.
“Traitor,” James muttered.
They started wandering down the corridor in a loose, laughing cluster.
And that was when they saw them.
Up ahead.
Five small figures.
First–years.
But not just any first–years.
Sirius stopped so abruptly James nearly walked straight into him.
“What,” James began—
Then he saw them too.
Regulus Black.
Barty Crouch Jr.
Evan Rosier.
Pandora Rosier.
Dorcas Meadowes.
All eleven years old.
All standing in the middle of the corridor.
And all looking like absolute disasters.
The Gryffindors slowed.
Confusion spread through the group.
Because something was very wrong.
Very wrong.
Barty Crouch Jr.—normally a sharp, composed little prodigy who treated magical creatures like complicated puzzles to solve—was crouched in front of a terrified kneazle.
“Please,” Barty said desperately, holding out a handful of leaves. “Please just stay still!”
The kneazle hissed and bolted down the corridor.
Barty groaned and clutched his hair.
“These animals don't listen, no, not one little bit. They run around out of control and throw their hissy fits.”
Sirius blinked slowly.
James whispered, “Is he… begging a kneazle?”
Barty kept rambling miserably.
“It's up to me to stop them, 'cause plainly you can see. It's got to be my destiny, and it's what my core is telling me.”
The Gryffindors stared.
Remus frowned.
“That’s… strange.”
Because Barty Crouch Jr. did not care about animals.
At all.
Behind him—
Evan Rosier was standing stiffly in front of a group of younger students.
He looked miserable.
He cleared his throat awkwardly.
Then he said in the flattest voice imaginable,
“I try to keep them laughing, put a smile upon their face.”
Silence.
No one laughed.
Evan looked pained.
“But no matter what I try, it seems a bit of a disgrace.”
James covered his mouth.
Sirius wheezed.
Evan kept going miserably.
“I have to entertain them, it's there for all to see. It's got to be my destiny, and it's what my core is telling me.”
The younger students slowly backed away.
Marlene whispered, horrified, “Is Evan Rosier trying to be funny?”
“Apparently,” Lily said faintly.
Pandora Rosier was kneeling beside a broken suit of armour with a wrench.
She looked furious.
“I don't care much for pickin' fruit and plowin' fields ain't such a hoot.”
She banged the wrench against a loose metal plate.
“No matter what I try, I cannot fix this busted water chute!”
Water suddenly sprayed from the armour’s helmet.
Pandora shrieked.
“I've got so many chores to do, it's no fun being me. But it has to be my destiny, 'cause it's what my core is telling me!”
Frank blinked.
“She’s… fixing things?”
“Trying,” Alice said.
Then—
There was a small explosion.
Everyone jumped.
Smoke billowed from the middle of the corridor.
And out of it staggered Regulus Black.
He was covered in soot.
His hair was sticking up.
His robes were singed.
In his hands was a bubbling potion that looked deeply concerning.
Regulus looked at it anxiously.
“Lookie here at what I made, I think that it's a draught of death.”
The Gryffindors froze.
Regulus peered into the potion.
“I know it doesn't look like much, I'm under some distress.”
It fizzed ominously.
Regulus looked around helplessly.
“Could y'all give me a hand here and help me fix this mess?”
The potion exploded.
Black smoke covered him.
Regulus coughed.
“My destiny is not pretty, but it's what my core is tellin' me.”
James slowly turned to Sirius.
“Why is your eleven–year–old brother making death potions.”
“I have no idea.”
Nearby—
Dorcas Meadowes had conjured a swirling storm cloud above her head.
Lightning cracked.
Frost spread across the floor.
She looked thrilled.
“I'm in love with weather patterns, but the others have concerns.”
The frost shot across the corridor.
Pandora screamed as ice climbed up her shoe.
“For I just gave them frostbite over top of their sunburns.”
Dorcas waved her wand again.
Snow fell.
Barty slipped on ice and crashed into the wall.
Dorcas frowned thoughtfully.
“I have to keep on trying, for everyone can see.”
At that point the Gryffindors could not remain silent.
James stepped forward.
“Okay.”
All five first–years turned.
James spread his arms.
“What is happening.”
They all exploded at once.
Barty pointed wildly.
“It's got to be—”
Evan shouted over him, “It's got to be!”
Pandora flailed with the wrench.
“My destiny—”
Dorcas yelled, “My destiny!”
Regulus waved his smoking cauldron.
“And it's what my core—”
Barty pointed at his chest.
“It's what my core—”
Then all five shouted together,
“Yes, it's what my core is telling me!”
Silence fell.
Absolute silence.
The Gryffindors stared.
James looked at Sirius.
Sirius looked at Remus.
Remus slowly closed his book.
Peter whispered, “What.”
Lily pressed her fingers to her temples.
Mary said faintly, “Did they all hit their heads?”
Fabian whispered, “I think they broke.”
Gideon whispered back, “All five of them.”
Frank stared at the frost–covered corridor.
Alice blinked at the smoke pouring off Regulus.
Marlene leaned toward Sirius.
“Your brother is on fire.”
Regulus sneezed soot.
Sirius stared at the five frantic first–years.
Then slowly said,
“…Moony.”
Remus sighed.
“Yes.”
“I think something went catastrophically wrong.”
Remus nodded.
“Very catastrophically.”
The corridor remained frozen in stunned silence.
Smoke drifted lazily from the blackened cauldron in Regulus Black’s hands.
Ice crept slowly along the stone floor from Dorcas Meadowes’s storm cloud, which continued hovering uncertainly above her head like it wasn’t quite sure where it belonged.
Water dripped steadily from Pandora Rosier’s unfortunate attempt at repairing the suit of armour.
And Barty Crouch Jr. sat on the floor with a kneazle paw print across his robes, staring miserably at the ceiling.
The Gryffindors simply… stared.
James Potter was the first to break the silence.
“…Right.”
He rubbed the back of his neck.
“Either we’ve all collectively gone mad,” he said slowly, “or the five of them have.”
“Neither explanation is comforting,” Remus murmured.
Peter was looking between the five younger students with wide eyes.
“They sounded so serious.”
“They were serious,” Lily said.
Sirius, however, wasn’t listening.
His grey eyes were locked on Regulus.
Because something about this was deeply wrong.
Not just the explosions.
Not just the soot.
Something fundamental.
Regulus coughed weakly and set the smoking cauldron down on the floor.
The eleven–year–old looked exhausted.
His shoulders drooped.
His pale face was grey beneath the soot.
And his hands were shaking.
Sirius frowned.
That was wrong.
Very wrong.
Because if there was one thing Sirius knew about his baby brother—
It was animals.
Regulus had always had animals around him.
Always.
When Sirius was ten and Regulus was nine, Sirius had watched a stray owl land directly on Regulus’s shoulder like it had known him its entire life.
When Regulus was six, the Black family’s vicious peacocks had followed him around the garden like loyal soldiers.
When he was eight, he’d calmly pulled a terrified kneazle out from under a carriage while their parents shouted about it.
Animals liked him.
No—
Animals adored him.
It was instinctive.
Natural.
They listened to him.
Which meant—
Sirius slowly turned his head.
And looked at Barty Crouch Jr., who was currently trying and failing to coax the kneazle back toward him.
The kneazle hissed again and bolted away.
Barty groaned.
Sirius blinked.
Then blinked again.
“…What.”
James glanced over.
“What?”
Sirius pointed slowly at Barty.
“Why,” he said carefully, “is he trying to handle animals?”
James shrugged.
“Maybe he likes them?”
Sirius turned slowly toward Regulus.
“Regulus likes animals.”
James froze.
“Oh.”
Remus looked up sharply.
Lily’s eyes narrowed.
“Wait.”
The Gryffindors began glancing between the five first–years again.
Slowly.
Carefully.
And the pattern started forming.
Mary pointed hesitantly toward Barty.
“Isn’t… he usually the one pulling pranks?”
James snapped his fingers.
“Yes!”
Peter nodded eagerly.
“Yeah! He told the Fat Friar that suit of armour was cursed last week!”
Fabian laughed.
“The Friar spent twenty minutes apologising to it!”
Gideon leaned forward.
“And he convinced Peeves the library was haunted.”
Frank frowned thoughtfully.
“But he’s trying to care for animals.”
They all turned.
And looked at Regulus.
Who was staring miserably into the ruined cauldron like it had personally betrayed him.
Lily spoke slowly.
“And Regulus…”
Sirius finished quietly.
“Is incredible with animals.”
Silence stretched again.
Then Marlene pointed at Evan.
“Rosier’s supposed to be terrifyingly good at dark magic.”
Remus nodded.
“Environmental magic especially.”
“Storms,” Lily said.
“Shadows,” Mary added.
“Curses,” Gideon said.
Everyone looked at Dorcas.
Who was currently trying to calm a violently spinning storm cloud.
“…But Dorcas is doing that,” Alice said faintly.
James looked at Pandora.
“And Pandora’s the mad scientist.”
Pandora was currently elbow–deep in the suit of armour.
“But Dorcas is the one who builds things,” Frank finished.
Remus inhaled slowly.
Understanding began settling over the group like a heavy fog.
“…Their skills,” he said carefully.
“They’re all aligned to their magical cores.”
Everyone turned to him.
Remus stood slowly.
“At birth,” he continued, “every witch and wizard develops a magical core. It determines magical affinity, instinctive skill alignment, magical temperament… even destiny.”
James frowned.
“…Yeah?”
Remus gestured toward the five miserable children.
“They’re behaving as though their cores are telling them to do something they’re not naturally aligned to.”
Lily’s eyes widened.
“Oh.”
Peter blinked.
“…Oh.”
James’s mouth fell open.
“Wait.”
He pointed at the five.
“You’re saying—”
Remus finished quietly.
“A spell.”
Silence.
Then Fabian said slowly,
“You mean…”
Gideon finished the thought.
“…their cores got swapped.”
Another long silence.
Everyone looked back at the five first–years.
And suddenly—
Everything made sense.
The frantic desperation.
The insistence.
The miserable attempts.
They weren’t confused.
They genuinely believed they were following their cores.
Lily looked stricken.
“Oh no.”
Frank swore under his breath.
“That’s not good.”
Alice’s voice was tight.
“If their cores are misaligned…”
Remus nodded grimly.
“Magical instability.”
Mary looked worried.
“That affects everything.”
“Magic,” Lily said.
“Physical health,” Remus added.
“Mental health,” Frank said quietly.
Sirius had already crossed the corridor.
He crouched in front of Regulus.
Up close, it was worse.
The younger boy looked pale.
Not just tired.
Drained.
Regulus blinked slowly at him.
“Sirius?”
His voice was faint.
Sirius’s chest tightened.
Regulus rarely looked fragile.
But right now—
He looked sick.
Exhausted.
Like something inside him was pulling the wrong way.
“What happened?” Sirius asked gently.
Regulus shook his head weakly.
“I… don’t know.”
He rubbed his eyes.
“I keep trying but nothing’s working.”
His voice wavered.
“I’m supposed to be good at this.”
Behind them, Barty sat slumped against the wall.
Evan stared blankly at his hands.
Pandora had given up on the armour.
Dorcas’s storm cloud flickered weakly before dissolving.
They all looked the same.
Drained.
Miserable.
Like their bodies were fighting something invisible.
James swallowed.
“…Blimey.”
Remus’s voice was firm.
“We need to fix this.”
Lily nodded immediately.
“Quickly.”
Frank looked worried.
“The longer a core stays misaligned—”
“—the worse the damage gets,” Remus finished.
Sirius stood slowly.
His jaw was tight.
His eyes were locked on Regulus.
His little brother looked like he could barely stand.
And Sirius Black had spent eleven years protecting him.
That instinct had never gone away.
Not once.
He turned to the others.
“Alright.”
His voice was sharp now.
Focused.
“We’re fixing this.”
James nodded immediately.
“Agreed.”
Lily pushed her sleeves up.
“Let’s start thinking.”
Behind them, the five first–years sat quietly on the cold stone floor.
Small.
Pale.
Exhausted.
And looking utterly lost.
The change was gradual.
But once the Gryffindors noticed it—
It was impossible to ignore.
The five first–years had stopped moving.
Not entirely.
But the frantic energy that had been driving them minutes ago had simply… drained away.
Like a candle burning out.
Barty Crouch Jr. sat against the stone wall, his head tilted back, breathing shallowly. His wand had slipped from his fingers and lay forgotten beside him.
Evan Rosier had folded in on himself, arms wrapped around his knees, staring blankly at the floor as though his thoughts were far away.
Pandora Rosier slumped beside the broken armour she’d been trying to repair, wrench loosely dangling from her fingers.
Dorcas Meadowes had slid down the wall until she was sitting on the cold stone floor, her back pressed against it, eyes half–closed.
And Regulus Black—
Regulus swayed where he stood.
Sirius saw it first.
Of course he did.
The older boy lunged forward just as Regulus’s knees gave out.
“Reg!”
He caught him before he hit the ground.
Regulus was frighteningly light in his arms.
The eleven–year–old sagged against him without resistance, head tipping weakly against Sirius’s shoulder.
For a moment Sirius just stared.
Because Regulus wasn’t reacting.
Not really.
His eyes were open.
But they looked… distant.
Unfocused.
“Sirius?”
It was barely a whisper.
Sirius’s stomach twisted violently.
“Hey,” Sirius said quickly, shifting his grip and lifting the smaller boy fully into his arms.
Regulus didn’t protest.
Didn’t cling.
Didn’t even move.
He simply slumped against Sirius like a doll with its strings cut.
“Reg, hey, stay with me,” Sirius murmured, his voice tight.
He started swaying instinctively, rocking slightly from side to side.
A motion so familiar he didn’t even realise he was doing it.
Regulus had been small once.
Very small.
Sirius had carried him like this before.
Years ago.
Back when Regulus had nightmares.
Back when Sirius could still sneak into the nursery and pick him up.
Sirius shifted his grip, one arm under Regulus’s knees, the other supporting his back.
“It’s alright,” he murmured quietly. “It’s alright, I’ve got you.”
Regulus’s head rolled weakly against his shoulder.
His eyes blinked slowly.
Too slowly.
Sirius swallowed.
“Shh,” he murmured, bouncing slightly as he walked. “It’s alright.”
Behind him, the other Gryffindors had gone very still.
Because the other four children weren’t doing much better.
Barty’s breathing had grown shallow.
Pandora had slumped completely onto her side.
Evan’s head had tipped back against the wall, his eyes half–closed.
Dorcas looked pale.
Very pale.
Frank crouched beside her quickly.
“Dorcas?”
No response.
Frank’s voice sharpened.
“Dorcas!”
Remus knelt beside Barty, pressing two fingers to the boy’s wrist.
His face went tight.
“The misalignment’s getting worse.”
Mary looked terrified.
“How fast?”
Remus exhaled slowly.
“Too fast.”
Alice knelt beside Pandora, shaking her shoulder gently.
Pandora barely reacted.
“Oh Merlin,” Alice whispered.
James ran a hand through his hair.
“Okay.”
His voice was tight with panic.
“Okay okay okay.”
He pointed at Fabian and Gideon.
“You two—library.”
The twins didn’t argue.
They bolted down the corridor instantly.
Mary grabbed Lily’s arm.
“I’ll help.”
“Go,” Lily said immediately.
Mary ran after them.
James turned to Peter.
“You help Remus run diagnostics.”
Peter nodded frantically and dropped to his knees beside Evan.
Remus was already muttering spells under his breath, wand moving in precise patterns.
Blue light flickered around Barty’s body.
The result made Remus grimace.
“What?” Peter asked nervously.
“The core energy is unstable,” Remus said quietly.
“How unstable?”
Remus didn’t answer.
Across the corridor, Sirius had moved away from the group.
He was pacing slowly now.
Back and forth.
Still holding Regulus.
Still rocking him gently.
“Stay with me,” Sirius whispered.
Regulus didn’t answer.
His head rested limply against Sirius’s shoulder.
Sirius adjusted his grip again, one hand sliding up to cradle the back of Regulus’s head.
His thumb brushed the boy’s hair.
Regulus’s breathing was shallow.
Uneven.
Sirius felt something cold settle in his chest.
“Reg,” he said quietly.
No response.
Sirius’s voice cracked slightly.
“Come on, Reg.”
He swayed again.
Rocking gently.
“Hey… hey… stay with me.”
James glanced over.
And immediately regretted it.
Because Sirius Black looked terrified.
Not angry.
Not annoyed.
Terrified.
He kept whispering to Regulus under his breath.
Soft shushing sounds.
Little murmured reassurances.
Like Regulus was still that tiny boy who used to hide behind Sirius during thunderstorms.
James swallowed.
Then Fabian and Gideon came sprinting back down the corridor.
Both of them were carrying stacks of books.
“Found stuff on magical cores!” Fabian shouted.
“Also spell misalignment!” Gideon added.
They dumped the books onto the floor.
Remus immediately started flipping through pages.
Lily knelt beside him.
“Anything?”
“Possibly,” Remus muttered.
Frank glanced over at Sirius again.
The older boy hadn’t stopped pacing.
He kept adjusting Regulus in his arms.
Bouncing slightly.
Murmuring softly.
Trying to keep him awake.
“Shh,” Sirius whispered.
His voice was hoarse now.
“You’re alright.”
Regulus didn’t react.
His head rolled slightly with Sirius’s movement.
Sirius’s grip tightened instinctively.
“You’re alright,” he repeated quietly.
Behind him, the Gryffindors tore through book after book.
Pages flipped rapidly.
Spells were whispered.
Diagnostics flashed.
Remus’s eyes scanned line after line.
James hovered anxiously beside him.
“Anything?”
Remus flipped another page.
“Maybe.”
“Maybe is good,” James said desperately.
Remus frowned.
“…If this is what I think it is.”
Lily leaned closer.
“What?”
Remus tapped a paragraph.
“A core displacement hex.”
James blinked.
“That sounds bad.”
Remus nodded grimly.
“It is.”
Across the corridor, Sirius finally stopped pacing.
He looked down at Regulus again.
The younger boy looked impossibly small in his arms.
Too pale.
Too still.
Sirius pressed his forehead briefly against Regulus’s hair.
Then he looked back at the others.
And for the first time since this started—
His voice shook.
“Fix it.”
The corridor had turned into a battlefield of books.
Ancient spell tomes lay open across the stone floor.
Loose parchment notes were scattered everywhere.
Wands glowed faintly as the Gryffindors cast diagnostic charms again and again, trying to confirm what Remus Lupin had just said.
The atmosphere had shifted.
The panic was no longer frantic.
Now it was sharp.
Focused.
Dangerous.
Because something was very, very wrong.
Remus sat cross–legged on the floor surrounded by books, flipping pages with controlled urgency.
Lily knelt beside him.
James paced back and forth.
Frank crouched beside Dorcas, running gentle diagnostic charms over her again.
Peter hovered anxiously beside Evan.
Fabian and Gideon kept digging through the growing pile of books.
Alice sat beside Pandora, brushing hair away from the younger girl’s face.
And Sirius—
Sirius had not moved far.
He was leaning against the corridor wall now, still holding Regulus in his arms.
Still rocking him slightly.
Still whispering quiet reassurances that Regulus probably couldn’t even hear.
Regulus’s head rested against Sirius’s shoulder.
His breathing was shallow.
Slow.
Too slow.
James stopped pacing.
“Moony.”
Remus didn’t look up.
“What is it.”
Remus exhaled slowly.
“I’m almost certain I know what spell did this.”
Everyone froze.
James’s voice went tight.
“…What spell.”
Remus finally looked up.
His face was pale.
“It’s called a Core Displacement Hex.”
Silence fell.
Even the rustle of pages stopped.
Peter blinked.
“A what?”
Remus pushed one of the books toward them.
It was old.
Very old.
The pages were yellowed and brittle.
“This spell forcibly detaches a witch or wizard’s magical core from its natural alignment.”
Lily frowned.
“You mean… their affinity?”
“Yes.”
Remus tapped the page.
“It disrupts the internal magical structure that determines magical instincts, specialization, magical growth… everything.”
James looked over at the five slumped children.
“…And swaps them.”
Remus nodded grimly.
“If multiple targets are hit simultaneously, the cores can be displaced into each other.”
Frank’s jaw tightened.
“That’s exactly what happened.”
Remus nodded again.
“Yes.”
Alice looked horrified.
“But they were trying to follow their cores.”
“Exactly,” Remus said.
“The body listens to the core. Always.”
Mary had returned with another stack of books.
She dropped them beside Gideon.
“So they’re instinctively trying to do what their new cores are telling them.”
Remus nodded.
“But their bodies aren’t built for it.”
Lily’s voice was quiet.
“That’s why they’re deteriorating.”
Remus didn’t answer immediately.
He glanced toward Sirius.
Toward Regulus.
The younger boy had gone completely limp in his brother’s arms.
Then Remus looked back at the others.
“Yes.”
James frowned.
“How long ago were they hit?”
Remus looked down at the book again.
Then at the five children.
He studied them carefully.
Barty’s shallow breathing.
Evan’s distant gaze.
Pandora’s pallor.
Dorcas’s trembling hands.
Regulus’s near unconsciousness.
Remus swallowed.
“…A few hours.”
James froze.
“That long?”
Remus nodded slowly.
“The symptoms escalate in stages.”
He tapped the book again.
“Stage one is confusion and instinctive misalignment.”
Lily nodded.
“That’s when we found them.”
“Stage two is magical instability,” Remus continued.
“Loss of magical control. Physical exhaustion.”
Frank looked down at Dorcas.
“That’s where they were ten minutes ago.”
Remus’s voice dropped slightly.
“Stage three is core collapse.”
The corridor went still.
James’s voice was very quiet.
“…Which stage are they in now?”
Remus looked at the five children again.
At their pale faces.
Their weak breathing.
Their empty eyes.
Then he answered.
“…The final one.”
The words hung in the air.
Heavy.
Unforgiving.
Peter whispered,
“What happens after the final stage?”
Remus hesitated.
Then he turned the book toward them.
And read.
“The magical core begins to burn itself out attempting to sustain the body’s life functions.”
Alice’s face went white.
“What?”
Remus nodded grimly.
“The core tries to keep the host alive.”
James blinked.
“That sounds good.”
Remus shook his head.
“It isn’t.”
Lily’s voice was tense.
“Why?”
Remus closed the book slowly.
“Because the core can’t sustain both the body and the misalignment.”
Silence filled the corridor again.
Frank’s voice was low.
“So what happens.”
Remus looked down at his hands.
“Eventually…”
He swallowed.
“The core burns itself out completely.”
Peter stared at him.
“…Meaning?”
Remus answered quietly.
“They lose their magic.”
The words landed like a hammer.
Mary covered her mouth.
“Forever?”
“Yes.”
Gideon whispered,
“They’d be squibs.”
Remus nodded.
“That was the original purpose of the spell.”
James frowned.
“…Purpose?”
Remus looked back at the old book.
“This hex is ancient.”
His voice was tight now.
“It was used centuries ago.”
Lily finished the thought quietly.
“To forcibly strip magic from people.”
Remus nodded.
“Yes.”
Alice looked back at Pandora.
“But… they’d still live, right?”
Remus’s silence answered the question before he spoke.
“They would live.”
Peter’s voice trembled.
“…But?”
Remus closed the book again.
“But the damage doesn’t stop when the magic burns out.”
James’s stomach sank.
Remus spoke carefully.
“The magical core regulates a wizard’s physical and mental stability.”
Frank swore under his breath.
“So if it burns out…”
Remus nodded.
“The body suffers.”
Alice whispered,
“How badly?”
Remus didn’t sugarcoat it.
“They’d be chronically ill.”
Mary looked sick.
“Physically?”
“Yes.”
“And mentally?” Lily asked quietly.
Remus nodded once.
“The brain is partly sustained by magical energy in magical humans.”
Silence again.
James ran both hands through his hair.
“So they’d survive.”
Remus nodded.
“Yes.”
“But barely.”
Across the corridor—
Sirius had gone very still.
He had been listening.
Every word.
His grip tightened slightly around Regulus.
Regulus didn’t react.
His head still rested limply against Sirius’s shoulder.
James finally forced the question.
“…How long do we have?”
Remus answered immediately.
“Not long.”
“How long,” James repeated.
Remus looked at the five children again.
Then said quietly,
“Maybe an hour.”
The words landed like a blade.
Sirius’s breath caught.
James whispered,
“Bloody hell.”
Frank looked furious.
“So we fix it.”
Remus nodded.
“Yes.”
James turned toward him.
“How?”
Remus hesitated.
Then sighed.
“That’s the problem.”
Lily leaned forward.
“What do you mean.”
Remus gestured toward the books.
“There’s no recorded cure.”
Silence.
James blinked.
“…None?”
Remus shook his head.
“The spell was outlawed before anyone bothered developing one.”
Peter’s voice cracked.
“So what do we do?”
Remus flipped open another book.
“However…”
Everyone leaned forward.
Remus tapped a few passages scattered across different pages.
“There are several spells that interact with magical cores.”
James frowned.
“Meaning?”
Remus looked up.
“I think…”
He hesitated.
“…if we combine the right spells in the right order…”
Lily finished softly.
“You might be able to force the cores back into place.”
Remus nodded slowly.
“Yes.”
Frank straightened.
“Then we do it.”
Remus’s voice was quiet but firm.
“I just need to find them.”
Across the corridor—
Sirius pressed his forehead briefly against Regulus’s hair.
His voice was barely more than a whisper.
“Hold on, Reg.”
He rocked him gently again.
“Just hold on.”
The corridor had descended into chaos.
Books were everywhere.
Open, stacked, scattered across the floor in frantic piles. Pages flipped rapidly under shaking hands as the Gryffindors searched through ancient spell indexes and half–forgotten magical theory texts.
Remus was hunched over three different books at once, his brow furrowed with concentration.
Lily was writing down sequences of spell structures on a scrap of parchment.
James paced so fast he nearly wore a groove into the stone floor.
Frank was double–checking diagnostic charms on the five first–years every thirty seconds.
Peter hovered nervously over Remus’s shoulder.
Fabian and Gideon had taken over the task of sprinting to the library and back whenever another possible reference appeared.
Alice and Mary kept turning pages with desperate speed.
And Sirius—
Sirius had not moved from where he sat on the floor with Regulus in his arms.
The younger boy had grown frighteningly still.
His breathing was shallow.
Barely there.
Sirius had stopped pacing.
Now he simply held him.
One hand cradling the back of Regulus’s head.
The other wrapped tightly around his waist.
Rocking slightly.
“Come on,” Sirius whispered hoarsely.
“Come on, Reg.”
Regulus didn’t respond.
His eyes had slipped closed.
Across the corridor—
Remus suddenly straightened.
“I’ve got three of them.”
Everyone snapped toward him.
James leaned over his shoulder.
“Three?”
Remus pointed at the parchment Lily had been scribbling on.
“The stabilisation charm.”
Lily nodded.
“The extraction spell.”
Frank added quickly,
“And the redirection binding.”
Remus tapped the page again.
“But we’re missing the final one.”
James blinked.
“What final one?”
“The reintegration trigger.”
Silence fell.
James stared.
“You’re telling me we’ve done all this and we’re still missing one spell?”
Remus’s voice was tight.
“Yes.”
Peter whispered,
“How long do we have?”
Frank checked Dorcas’s pulse again.
His face went pale.
“…Ten minutes.”
The words detonated in the corridor.
Everyone started moving faster.
Mary flipped through another book frantically.
Fabian and Gideon dumped yet another stack of library texts onto the floor.
Lily scanned spell indexes with lightning speed.
James raked a hand through his hair.
“Come on—come on—come on—”
Across the corridor Sirius wasn’t paying attention to any of it.
His world had narrowed to the small boy in his arms.
Regulus’s skin felt cold.
Too cold.
“Stay with me,” Sirius whispered.
His voice trembled now.
“Please.”
Five minutes.
Remus slammed another book shut.
“Not here.”
Lily grabbed another.
“Try the theoretical sections.”
James was pacing again.
Peter was nearly hyperventilating.
Frank kept checking pulses.
Three minutes.
Sirius’s breathing was uneven now.
“Reg,” he whispered.
Nothing.
“Reg.”
Two minutes.
Mary gasped suddenly.
“WAIT.”
Everyone turned.
She was pointing wildly at a page.
“I think I found it!”
Remus lunged across the floor and grabbed the book.
His eyes scanned the page.
Then widened.
“That’s it.”
James clapped his hands once.
“DO IT.”
There was no hesitation.
Remus, Lily, James, Frank, and Fabian immediately moved into position around the five first–years.
Remus’s voice was sharp.
“Stabilisation first.”
Five wands lifted.
A burst of silver magic struck Barty.
Then Evan.
Then Pandora.
Then Dorcas.
One after another.
The children didn’t move.
“Extraction!” Remus barked.
Another sequence of spells shot from their wands.
The air vibrated.
Energy crackled around the five slumped bodies.
“One minute,” Frank said tensely.
The corridor filled with humming magical pressure.
“Redirection binding!”
Golden threads of magic wrapped around the five children.
Holding.
Guiding.
Preparing.
Sirius was still across the corridor.
Still holding Regulus.
“Now the final spell!” James shouted.
Remus’s wand flicked—
Then stopped.
“…Wait.”
Everyone froze.
Remus looked around.
Four of the five children had been hit.
But Regulus—
Regulus hadn’t.
James’s voice cracked.
“Remus.”
Sirius looked up.
“What.”
Remus’s face went white.
“We haven’t cast the sequence on Regulus yet.”
Sirius shot to his feet instantly.
“WHAT?”
Regulus sagged weakly in his arms.
James’s voice was tight.
“Thirty seconds!”
Sirius was already striding toward them.
“FIX IT!”
Remus raised his wand.
But Sirius shoved Regulus forward.
“NOW!”
The spells fired.
Silver light struck Regulus.
Then the extraction spell.
Then the binding.
The moment the final spell hit—
Everything changed.
All five children gasped sharply.
Then—
Light exploded from their chests.
Directly above their hearts.
Five distinct colors.
Barty glowed soft lilac–pink.
Evan burned amber.
Pandora shone deep green.
Dorcas flickered icy blue.
And Regulus—
Regulus blazed neon yellow.
The Gryffindors stepped back in shock.
The lights pulsed.
Brighter.
Brighter.
Then—
The glowing shapes began rising.
Slowly pulling free from each child’s chest.
Pure magical cores.
Visible.
Floating.
The five children went completely limp.
Like their bodies had been emptied.
Sirius’s heart nearly stopped.
“REG—”
But the cores were already moving.
The lilac–pink light drifted toward Regulus.
The amber light slid toward Barty.
The deep green glow moved to Dorcas.
The icy blue spark floated toward Evan.
And the neon yellow core—
It returned to Pandora.
One by one—
The glowing lights sank back into their rightful bodies.
Then everything went still.
The corridor held its breath.
The five children lay motionless.
Ten seconds passed.
Twenty.
Thirty.
Sirius’s voice was shaking.
“Why aren’t they moving.”
Then—
BOOM.
Raw magic erupted outward.
A massive shockwave blasted through the corridor.
The Gryffindors were thrown backwards.
Books flew everywhere.
James slammed into the wall.
Peter skidded across the floor.
Fabian and Gideon crashed into a suit of armour.
Sirius barely kept his footing.
The magic pouring from the five children was enormous.
Wild.
Bright.
Alive.
Their cores were realigning.
Rebuilding.
Correcting.
Then—
Evan Rosier groaned.
He sat up slowly.
At the same time the air around him erupted into violent weather.
Wind whipped down the corridor.
Frost spread across the stone.
Lightning flickered.
Evan blinked.
Then calmly lifted a hand.
The storm immediately settled.
Controlled.
Perfect.
Nearby Barty rolled onto his back with a groan.
“Ugh.”
Pandora pushed herself upright beside him.
“Everything hurts.”
Dorcas sat up too, rubbing her head.
A loose piece of broken armour above her suddenly tipped—
Then snapped back into place midair.
Dorcas flicked her wand lazily.
The metal reshaped and repaired itself perfectly.
“Better,” she muttered.
Barty grinned.
“Well that was dramatic.”
He pointed at Pandora.
“You exploded.”
Pandora snorted weakly.
“You exploded.”
Barty smirked.
“Worth it.”
Pandora giggled despite herself.
Then her eyes landed on the blackened cauldron.
Her entire expression sharpened instantly.
“Oh.”
She crawled over and peered inside.
“Huh.”
She sniffed the potion residue.
“Interesting.”
Pandora began muttering to herself.
“If you added crushed moonstone and altered the simmer temperature you could stabilise the reaction…”
She started sketching imaginary changes in the air with her finger.
Dorcas groaned.
“Pandora please.”
But the biggest reaction came from Regulus.
His core had burst with the brightest light of all.
And the moment it settled—
Something incredible happened.
The corridor filled with movement.
Hundreds of tiny wings.
Scuttling legs.
Soft fur.
Feathers.
Spiders dropped from the ceiling.
Butterflies fluttered in through the windows.
A kneazle sprinted down the corridor.
Several mice appeared from nowhere.
A cluster of beetles crawled along the floor.
Birds landed along the windowsills.
Every creature in the area seemed to rush toward the same place.
Regulus.
The small boy wriggled weakly as animals began piling onto him.
“Wait—!”
A butterfly landed on his nose.
A spider climbed his sleeve.
A mouse curled against his shoulder.
A kneazle climbed directly into his lap.
Regulus blinked sleepily.
“Oh.”
He immediately started gently petting the kneazle.
“Okay okay—calm down.”
More creatures gathered.
“Everyone relax.”
His voice was soft.
Gentle.
“There's enough room.”
The animals settled almost instantly.
Climbing onto him.
Curling around him.
Nuzzling against him.
The Gryffindors stared in absolute shock.
Then—
Relief crashed over them like a wave.
James slid down the wall laughing weakly.
“Oh thank Merlin.”
Lily leaned against the wall breathing hard.
Mary covered her face.
Frank sat heavily on the floor.
Alice wiped her eyes.
Remus exhaled slowly.
Across the corridor Sirius just stood there.
Staring at Regulus.
At the small boy now surrounded by half the castle’s wildlife.
Alive.
Breathing.
Safe.
Then Sirius finally let out the breath he’d been holding.
And the panic drained from his shoulders.
For a long moment after the magical eruption faded, the corridor was filled with nothing but the soft rustle of wings and the quiet breathing of people who had very nearly witnessed something irreversible.
Then the five first–years began to move.
Barty was the first to push himself upright.
“Ugh,” he groaned, rubbing the back of his head. “What just—”
He tried to stand.
His legs wobbled immediately.
“Woah—”
Evan grabbed his sleeve before he tipped sideways.
“Careful,” Evan muttered, though he looked just as unsteady himself.
Dorcas sat up more slowly, blinking hard as if her vision hadn’t quite caught up with reality yet.
Pandora rolled onto her stomach, then pushed herself up with a confused little huff.
And Regulus—
Regulus was still sitting on the floor.
A kneazle curled in his lap.
Three mice pressed against his legs.
A pair of butterflies fluttering lazily around his hair.
One of them had landed directly on his cheek.
Another rested in his curls.
And Regulus, still looking half–dazed, hugged a small bundle of fur to his chest.
“…Oh.”
The animals did not leave him.
If anything, more seemed to gather.
The kneazle purred loudly.
A beetle climbed onto his sleeve.
Several moths drifted toward him like he was a lantern.
Regulus blinked at them slowly.
“…Hello.”
He reached up instinctively and let one of the butterflies crawl onto his finger.
Across the corridor—
The Gryffindors stared.
Then Sirius moved.
Fast.
He crossed the distance in seconds and dropped to his knees in front of Regulus.
“Reg!”
Before the younger boy could even react, Sirius grabbed him and pulled him into a crushing hug.
Regulus squeaked faintly as he was lifted right off the floor.
The kneazle protested but stayed clinging to his robes.
The butterflies scattered briefly before settling again.
Sirius buried his face against Regulus’s hair.
“Thank god,” he muttered hoarsely.
His hands kept moving restlessly—petting Regulus’s hair, brushing soot off his robes, holding the back of his head like he needed to confirm the boy was real.
“Thank god, thank god.”
Regulus squirmed.
“Sirius—!”
His cheeks puffed immediately in protest.
“Sirius stop!”
But Sirius just hugged him tighter.
“Merlin’s beard,” Sirius breathed.
“You’re okay.”
Regulus wriggled helplessly in his arms.
“You’re squishing me!”
His cheeks puffed out into a dramatic pout.
A butterfly landed directly on his nose.
Regulus crossed his eyes trying to look at it.
“Sirius—!”
Sirius kissed the top of his head.
Then again.
Then pressed another quick smooch to the side of his temple.
“You scared the hell out of me.”
Regulus whined loudly.
“I don’t even know what happened!”
Behind them, the other Gryffindors were already moving again.
Remus knelt beside Barty, wand raised.
“Hold still.”
Barty frowned.
“Why?”
Blue diagnostic light flashed across him.
Barty blinked.
“…What’s that for?”
“Checking your magical structure,” Remus said calmly.
Barty squinted suspiciously.
“I feel fine.”
Frank was already checking Evan.
“Pulse is normal again.”
Evan flexed his fingers slowly.
“…My magic feels weird.”
Then he lifted his wand.
A small swirl of wind flickered into existence automatically.
Evan blinked.
“…Oh.”
He snapped his fingers experimentally.
The wind spiraled perfectly into a tight vortex and then vanished.
Evan looked surprised.
“That worked.”
Nearby Dorcas tapped a cracked stone tile with her wand.
It immediately repaired itself.
Dorcas blinked.
“…Oh.”
Pandora was still staring at the ruined potion cauldron.
She leaned closer.
Then sniffed the residue again.
“Huh.”
She squinted thoughtfully.
“You could stabilise the reaction if you altered the catalyst structure…”
She paused.
“…Oh.”
Pandora blinked.
“…My brain works again.”
Meanwhile Sirius was still holding Regulus.
Very tightly.
Regulus wriggled again.
“Sirius!”
Sirius ignored him and kept muttering under his breath.
“Merlin, you were barely breathing.”
“I was breathing!”
“You were not.”
“I was!”
“You looked like a corpse!”
Regulus gasped indignantly.
“I did not!”
“You did!”
Regulus puffed his cheeks again.
Several butterflies fluttered around his face.
One landed in his hair.
Sirius stared at him.
Then said very seriously,
“How could anyone want to hurt you.”
Regulus blinked.
“What?”
Sirius gestured vaguely at his face.
“You’re tiny.”
Regulus frowned.
“I’m not tiny.”
“You are.”
“I’m eleven!”
“You’re small!”
Regulus glared.
“I’m normal sized!”
“You’ve got butterflies in your hair!”
“That’s not my fault!”
James finally walked over.
He crouched beside them.
“You lot feeling alright?”
Five confused first–years stared at him.
Barty spoke first.
“…Why are all of you staring at us like we exploded?”
Pandora nodded.
“Also why are there books everywhere?”
Dorcas added,
“And why do I feel like I slept for a week?”
Remus glanced at the others.
Then sighed.
“…You don’t remember what happened.”
Five blank stares answered him.
Regulus looked up from Sirius’s arms.
“…Did something happen?”
The Gryffindors exchanged looks.
Then Lily spoke carefully.
“A spell hit you earlier.”
Barty frowned.
“What spell?”
Remus answered quietly.
“A core displacement hex.”
Silence.
The five first–years stared.
Then Pandora’s eyes widened.
“…Oh.”
Evan’s expression darkened immediately.
Dorcas looked horrified.
Regulus blinked.
“…Wait.”
Barty’s face went pale.
“You mean—”
Remus nodded.
“It swapped your magical cores.”
All five froze.
Pandora spoke first.
“…That explains a lot.”
Regulus looked confused.
“…Who would even do that?”
The five first–years looked at each other.
Then Dorcas muttered quietly,
“…We know.”
The Gryffindors leaned forward instantly.
James’s voice sharpened.
“Who.”
Evan’s jaw clenched.
“A fifth–year.”
Pandora nodded slowly.
“She was being arrogant.”
Barty rolled his eyes.
“We corrected her on a spell structure.”
Dorcas crossed her arms.
“She got annoyed.”
Regulus frowned.
“…Really annoyed.”
Evan’s voice was flat.
“She cast the hex.”
The corridor went silent again.
James blinked.
“…On purpose?”
Barty nodded grimly.
“She knew exactly what it was.”
Pandora added quietly,
“She said she wanted to teach us a lesson.”
The Gryffindors went very still.
Frank’s voice was dangerously calm.
“She knew what the spell did.”
Evan nodded once.
“Yes.”
Remus’s expression hardened.
“…You’re eleven.”
Pandora shrugged faintly.
“She wanted to prove she was better than us.”
Mary looked furious.
“That’s monstrous.”
Alice whispered,
“You could have died.”
Sirius had gone very quiet.
He was still holding Regulus.
But his expression had changed.
His eyes were dark.
Cold.
“…Who.”
Dorcas hesitated.
Then said the name.
The reaction was immediate.
James swore loudly.
Frank’s jaw clenched.
Lily looked furious.
Fabian muttered,
“She’s dead.”
Gideon nodded.
“Completely dead.”
Sirius looked like he might actually commit murder.
“I’m going to kill her.”
“Sirius,” Remus warned.
“I mean it.”
Sirius looked down at Regulus again.
At the tiny boy in his arms.
At the butterflies still resting in his curls.
At the animals still curled against him.
His voice dropped.
“She nearly killed him.”
Regulus blinked up at him.
“I’m fine.”
Sirius ignored him.
“He’s tiny.”
“I’m not tiny!”
“He’s got cheeks!”
Regulus gasped.
“My cheeks are normal!”
“And butterflies!”
“I can’t control that!”
“And look at him!”
Sirius gestured dramatically.
“He’s adorable!”
Regulus turned red.
“SIRIUS!”
The Gryffindors were half–laughing now despite the tension.
James shook his head.
“Alright.”
Then he glanced at the five children again.
“…Those core colours though.”
Everyone looked back at them.
Because the glow from earlier had been unmistakable.
Remus folded his arms thoughtfully.
“Core colours reflect magical identity.”
Pandora looked intrigued.
“…Really?”
Remus nodded.
“Barty’s was amber.”
Barty blinked.
“What does that mean?”
Remus shrugged slightly.
“Clever magic. Adaptability. Trickster energy.”
Barty grinned.
“That checks out.”
Remus continued.
“Evan’s was icy blue.”
Evan frowned.
“…Weather magic?”
“Environmental dominance,” Remus said.
“Complex magic structures.”
Dorcas tilted her head.
“And mine?”
“Deep green,” Remus said.
“Creation magic. Repair magic. Builders.”
Dorcas smiled faintly.
Pandora raised her hand eagerly.
“What about mine?”
“Neon yellow,” Remus said.
“Experimental magic.”
Pandora beamed.
“Mad science.”
Remus nodded.
“Exactly.”
Finally he looked at Regulus.
Soft lilac–pink.
Remus smiled slightly.
“That one’s rare.”
Sirius looked curious.
“What does it mean?”
Remus glanced at the kneazle curled in Regulus’s lap.
At the butterflies resting in his hair.
At the mice cuddled against his sleeves.
“…Natural affinity with living creatures.”
Regulus blinked.
“Oh.”
The kneazle purred louder.
Sirius hugged him again.
“See?”
Regulus groaned.
“Sirius stop!”