The kitchen of Number Twelve, Grimmauld Place had been unusually peaceful that afternoon, the kind of peace that Harry had slowly come to realise was almost impossible to find in the lives they led, because even when everyone was sitting together around the same table, eating the same food and discussing ordinary things, there was always something lurking beneath the surface, some distant threat or unfinished battle that prevented anyone from truly relaxing, yet for once Harry had managed to push all of that aside.
He had spent the better part of the morning training.
Not because anyone had forced him to, nor because there was some imminent battle that demanded his attention, but because training had become something deeply ingrained within him, a habit that had followed him through every life he had lived and every world he had visited, from the battlefields of Pandora to the frozen plains of Narnia, from the brutal world of the Saiyans to the war-torn kingdoms of the Four Nations, and even now, despite being returned to the body of his sixteen-year-old self, Harry could still feel the echoes of every version of himself living within his mind.
He had trained his body until his muscles ached, practised his bending until the elements responded almost instinctively, and then spent several hours working with ki, carefully regulating the energy flowing through his body while simultaneously maintaining magical shields around himself.
It was exhausting.
It was also strangely comforting.
For Harry, training had never simply been about becoming stronger.
It was about control.
Control over his emotions.
Control over his abilities.
Control over the part of himself that had, on more than one occasion, been capable of terrifying destruction.
When Harry finally decided that he had pushed himself far enough for one day, he made his way upstairs, changed into clean clothes and wandered toward the Black family library.
He had initially intended to continue reading, but when he entered the room, he found Sirius sitting in one of the enormous leather chairs beside the fireplace, a book resting open in his lap.
Sirius looked up immediately.
"Finished destroying the training room?"
Harry raised an eyebrow.
"I didn't destroy anything."
"That's what you said last time."
"I repaired it."
"After destroying it."
Harry smiled.
"Details."
Sirius snorted before closing the book and placing it on the table beside him.
For a few moments, neither of them spoke.
Harry eventually moved toward one of the shelves and began examining the titles, his fingers running across the spines of ancient books whose covers had been worn smooth by generations of Black family members.
"Remus told me something interesting yesterday," Sirius said casually.
Harry glanced over his shoulder.
"That sounds dangerous."
"He said you asked him about spell creation."
Harry turned fully.
"I did."
Sirius leaned back.
"Why?"
"I've been thinking about it."
"That's usually how trouble starts."
Harry laughed quietly.
"I mean it seriously."
"So do I."
Harry rolled his eyes and Sirius grinned.
"I've always wanted to create my own spells," Harry admitted. "But I never really had the time to learn how."
Sirius's expression became thoughtful.
"James and I experimented a lot when we were younger."
"That sounds terrifying."
"It was."
Harry waited.
Sirius smiled.
"We were actually quite good at it."
"Somehow I doubt that."
"You wound me."
"You survived being friends with my father."
"Exactly. That proves my point."
Harry laughed again, and Sirius's expression softened slightly.
For a moment, the conversation shifted naturally toward James.
Sirius began telling Harry stories about his father that Harry had never heard before, stories that Remus had apparently been saving because, as Sirius explained with great indignation, Remus had always been "far too sensible" to tell them.
There were stories about James and Sirius sneaking out after curfew, experimenting with charms that had nearly resulted in them being suspended, attempting to enchant their broomsticks to fly themselves and accidentally sending one through a classroom window, and once, according to Sirius, trying to create a spell that would make an entire plate of roast potatoes reproduce endlessly.
"It worked," Sirius insisted.
"It couldn't have."
"It did."
"Then why don't you have infinite potatoes?"
"Because McGonagall found us."
Harry stared at him.
"That explains everything."
Sirius chuckled.
Eventually, however, the conversation returned to spell creation.
"You'll want to start with Arithmancy," Sirius said, becoming more serious. "Spell creation isn't just about waving a wand and shouting something that sounds impressive."
Harry nodded.
"You need to understand the mathematics behind magical intent," Sirius continued. "The relationship between the caster, the wand, the magical structure of the spell and the desired result."
"Ancient Runes?"
"Definitely."
Sirius pointed toward a section of the library.
"There are several books there that might help you. You'll want The Mathematical Foundations of Magical Construction, Runic Theory and Applied Spellcraft, and there's an old Black family text called The Architecture of Magical Intent."
Harry's eyes narrowed with interest.
"Anything on Alchemy?"
Sirius smiled.
"Of course."
Harry immediately moved toward the shelves.
Sirius watched him.
"Harry."
"Yes?"
"Don't read everything in one sitting."
Harry paused.
"I wasn't planning to."
"Good."
Harry glanced toward the shelves.
"Maybe two."
"Harry."
"I'm joking."
Sirius narrowed his eyes.
Harry smiled innocently.
"Mostly."
Over the following two days, Harry proceeded to do exactly what Sirius had told him not to do.
He read everything.
The difference was that Harry no longer possessed the mind of an ordinary sixteen-year-old.
He had lived through countless experiences, learned from scholars and warriors, studied magic in multiple worlds and possessed memories that stretched across centuries of subjective experience.
His mind had become something almost impossible to compare to his former self.
Arithmancy came first.
Harry devoured it.
The mathematical structure behind spell construction fascinated him, particularly the way numbers could be used to establish magical relationships between intention and reality.
Ancient Runes followed.
Harry studied the foundations of magical language, discovering that many spells were not simply spoken commands but carefully structured magical concepts whose incantations acted as verbal anchors.
Alchemy proved even more fascinating.
He studied the interaction between magical energy, matter, transformation and life.
Finally, he began studying the actual creation of spells.
And slowly, Harry began to understand something.
Magic was not as rigid as he had once believed.
The spells taught at Hogwarts were simply established pathways.
They were not the only pathways.
Harry began experimenting.
Carefully.
Methodically.
He designed magical structures that combined his knowledge of healing magic with the regenerative principles he had learned across his various lives.
One spell in particular occupied most of his attention.
A spell capable of restoring a lost limb.
Not simply repairing an injury.
Not conjuring a temporary replacement.
Actually regenerating the missing tissue.
Harry called it Regenitus Corpus.
He had not yet tested it.
He had no intention of doing so without a suitable subject.
Unfortunately, fate had apparently decided that it would provide one.
Harry had just returned to the kitchen after his training when he immediately noticed something was wrong.
The room was unusually quiet.
Everyone was there.
Sirius.
Remus.
Molly.
Arthur.
Ron.
Hermione.
Ginny.
The twins.
Several members of the Order.
Yet nobody was speaking.
Then Harry saw Dumbledore.
The headmaster was being guided into the room by Snape.
Harry froze.
Dumbledore looked terrible.
His face was pale.
His movements were stiff.
And his right arm,
Harry's eyes immediately locked onto it.
The hand and forearm were black.
Not bruised.
Not burned.
Blackened.
The flesh appeared almost dead.
Harry's instincts immediately recognised the signs.
Dark magic.
Powerful dark magic.
Harry stepped forward.
"What happened?"
Snape's expression darkened.
"Ask the headmaster."
Dumbledore gave him a tired look.
"Severus."
"No."
Snape's voice was sharp.
"Absolutely not."
Everyone looked toward him.
Snape's eyes were furious.
"The headmaster decided that he could investigate a suspected Horcrux alone."
Harry's stomach dropped.
Dumbledore remained silent.
Snape continued.
"He found it."
Harry's eyes widened.
"And?"
Snape's expression became grim.
"He destroyed it."
"Then what's wrong with his arm?" Hermione asked.
Snape looked toward Dumbledore.
"The Horcrux was protected."
Harry's expression hardened.
"What kind of protection?"
"A curse."
Dumbledore finally spoke.
"A particularly unpleasant one."
"How unpleasant?" Ron asked nervously.
Snape's face became even darker.
"The curse has already spread."
Silence.
Harry stared at Dumbledore's arm.
"How long?"
Dumbledore looked at him.
"Albus," Sirius said quietly.
Dumbledore sighed.
"Approximately one year."
The room erupted.
"ONE YEAR?"
Sirius immediately stepped forward.
"You said you had time!"
"I do."
"That's not enough!"
"Less than a year," Snape corrected.
The room went silent.
Harry stared at the blackened arm.
Something inside him became very still.
He remembered Narnia.
The battlefield.
Pandora.
The Saiyan homeworld.
The Four Nations.
Every life had taught him something.
Every life had shown him the same lesson.
Sometimes, waiting was the worst decision a person could make.
Harry slowly stepped forward.
Dumbledore noticed.
"Harry?"
"I'm sorry, Headmaster."
Dumbledore frowned.
"For what?"
Harry raised his wand.
"Harry, what are you..."
"Petrificus Totalus."
Dumbledore froze.
Harry immediately followed with a Silencing Charm.
The room erupted into confusion.
"Harry!"
"What are you doing?"
"Stop!"
Harry ignored them.
His eyes were fixed upon Dumbledore.
The headmaster's eyes widened.
Harry raised his wand.
"Diffindo."
The spell struck.
The blackened forearm separated cleanly from Dumbledore's body.
For a split second, everyone froze.
Then Harry moved.
His wand traced a slow clockwise spiral over the severed limb.
The magical pattern was one Harry had spent days designing.
A spell that did not simply repair.
A spell that instructed the body to remember.
To rebuild.
To restore.
Harry flicked his wand sharply upward.
"Regenitus Corpus."
The room went silent.
A faint silver-gold light emerged from the wound.
The magic spread.
First, the injury sealed.
The bleeding stopped.
Dumbledore's life force stabilised.
Then the regeneration began.
Bone formed first.
Slowly.
Precisely.
The skeletal structure rebuilt itself from the shoulder downward.
Then came nerves.
Muscle.
Blood vessels.
Tendons.
Skin.
The process was neither violent nor grotesque.
It was almost beautiful.
Like watching a tree grow in fast motion.
Within thirty seconds, a complete forearm and hand had formed.
Dumbledore's arm was restored.
Completely.
The blackened corruption was gone.
The room remained silent.
Harry lowered his wand.
"Finite."
The Petrification Charm vanished.
Dumbledore immediately moved.
His restored hand flexed.
Once.
Twice.
His fingers curled into a fist.
He stared at it.
Then he looked at Harry.
"How?"
Harry swallowed.
"I've been studying spell creation."
Dumbledore continued staring.
"How?"
Harry gestured toward the arm.
"I created the spell."
Sirius stared.
"You created that?"
Harry nodded.
"Yes."
Hermione looked horrified.
"Harry, you cut off his arm!"
"It was already dying."
"You could have killed him!"
"I know."
Harry's voice was quiet.
"I calculated the risks."
Everyone stared at him.
Harry looked toward Dumbledore.
"If I was wrong, I would have failed."
Dumbledore examined his hand again.
"But you weren't."
"No."
Harry looked down.
"I wasn't."
Dumbledore slowly stood.
He moved his arm.
No pain.
No stiffness.
Nothing.
It was as if the curse had never existed.
Snape stared at Harry with an expression that was difficult to interpret.
"That," he said slowly, "should not be possible."
Harry looked at him.
"Apparently it is."
Snape's eyes narrowed.
Harry shrugged.
"I've had a lot of practice doing impossible things."
The twins exchanged a look.
Fred leaned toward George.
"We're going to need a bigger notebook."
George nodded.
"Definitely."
Molly, however, was still staring at Dumbledore.
"Albus."
"I'm fine, Molly."
"You lost your arm!"
"And gained it back."
"That's not the point!"
Sirius finally seemed to recover from his shock.
He stared at Harry.
"Harry."
"Yes?"
"You just created a spell capable of regenerating lost limbs."
"Apparently."
"From scratch."
"Yes."
"And you tested it on Dumbledore."
Harry paused.
"When you put it like that, it sounds irresponsible."
"It was irresponsible!"
"Technically, it worked."
"That's not helping!"
Remus finally spoke.
"Harry."
Harry looked toward him.
Remus's expression was unusually serious.
"How long have you been working on that spell?"
"Two days."
The entire room stared.
"Two days?"
Harry nodded.
Hermione looked like she was struggling to process the information.
"You read all those books in two days."
"Yes."
"And then created a spell."
"Yes."
"That can regenerate an entire limb."
"Yes."
Hermione stared at him.
Harry smiled awkwardly.
"Are you going to be angry?"
Hermione opened her mouth.
Closed it.
Opened it again.
"No."
Harry relaxed.
"Good."
"I'm going to be furious later."
Harry's shoulders dropped.
"That's fair."
Dumbledore finally smiled.
It was a tired smile.
But it was genuine.
"Harry."
"Yes, Headmaster?"
"I believe I owe you my life."
Harry shook his head.
"No."
Dumbledore raised an eyebrow.
"You owe me a lecture."
Harry blinked.
"A lecture?"
"Several, I imagine."
Harry sighed.
"Right."
Dumbledore looked toward his restored arm.
"But I suspect those lectures can wait."
Sirius suddenly burst out laughing.
Harry looked at him.
"What?"
Sirius wiped his eyes.
"Nothing."
"You're laughing at me."
"Of course I am."
"Why?"
"Because you have just spent two days reading books, invented a revolutionary healing spell, chopped off Dumbledore's arm and then complained about getting a lecture."
Harry considered that.
"That does sound like me."
The room slowly began to relax.
The initial terror began to fade.
But nobody forgot what had happened.
Because the implications were enormous.
Harry had not simply created a new spell.
He had created something that could change magical medicine forever.
The ability to regenerate lost limbs.
The ability to restore soldiers.
The possibility of reversing injuries that had previously been considered permanent.
And Harry had done it at sixteen.
Dumbledore looked around the room.
"Perhaps," he said quietly, "we should discuss exactly what Harry has created."
Harry's expression immediately became wary.
"Oh, no."
Hermione looked at him.
"What?"
"I know that look."
"What look?"
"The 'Harry has accidentally changed the world and now we need to have a meeting about it' look."
Dumbledore smiled.
"I assure you, Harry, this is merely the beginning."
Harry groaned.
The twins immediately began laughing.
And somewhere within the room, even Snape looked faintly amused.
Harry glanced at Dumbledore's restored arm.
Then at his own wand.
For the first time, he truly began to understand what his knowledge could mean.
He had spent years learning how to fight.
How to survive.
How to destroy.
But now he had discovered something far more important.
He could create.
And perhaps, for the first time in his many lives, Harry Potter had finally found something that frightened him more than his own power.
The possibility of what he might do with it.