Source : Webnovel
Synopsis :
Expelled from Hogwarts. Imprisoned in Azkaban. Forgotten by the world.
Sagres Greengrass was a name whispered in the Wizarding World with fear and awe.
A half-blood from a pure-blood family. A prodigy who created spells no one dared speak aloud. A genius who crossed every line in pursuit of knowledge—and paid the price.
Branded dangerous, he vanished into the shadows of Azkaban.
Five years later, he returns—not as a student, but as a professor.
Sagres Greengrass is a transmigrator.
As a member of a pure-blood family in the magical world, his first experience of magic came from a Cruciatus Curse cast by his mother.
When he wanted to seek help from his father, he found out that his father was a Death Eater.
Imprisonment in Azkaban did not leave him with madness and corruption, but rather a kind of chilling elegance.
With the power of forbidden knowledge, a mind sharpened by torment, and secrets only a dark wizard could know…
The Dangerous Genius is back.
Chapter 01: It's time to leave Azkaban
The cold and damp Azkaban Prison stood atop a cliff on a lonely island in the North Sea.
CRASHHH! Waves slammed against jagged rocks far below, sending salt-spray hissing into the wind.
WHOOSH… A sharp gust of sea air howled through the narrow iron window. Dementors floated silently in the sky above, their robes fluttering like torn shadows.
Inside a shadowy cell, Sagres Greengrass sat unmoved on a stone bed.
A slender wand rested between his fingers, the tip glowing faintly silver.
Flip-flip-flip.An old, tattered magical book hovered mid-air, its pages turning in a blur as invisible forces rearranged the runes etched across them.
CLAAACK.The heavy cell door creaked open, metal grinding against stone.
Sagres did not flinch.
His wand continued to move.
"What a 'great' surprise," he said calmly, eyes still lowered. "Since when did Azkaban start allowing visitors?"
"For an old man like me, there are always some privileges."
Dumbledore walked into the cell with a smile, his blue eyes observing Sagres through his half-moon spectacles. His robes shimmered softly in the dim light, starkly out of place amid the gloom.
"Looks like they didn't assign you a roommate," Dumbledore said, placing a bag of lemon sherbets on the stone table.
Sagres's fingers moved slightly, and the magical book in the air turned to ash and drifted down.
He looked up at the old man, his gaze calm. "There are plenty of empty cells in Azkaban, Headmaster."
"But they didn't even take your wand?" the old man said, blinking playfully.
"I understand your confusion. After all, it was you who personally cast the Trace on my wand. But now…" He waved the wand in his hand, his calm tone revealing a trace of pride. "Even the Dementors can't detect the magical signature from it."
Dumbledore didn't reply.
Instead, he looked around the cell, eventually settling his gaze on the anti-magic stone bricks of the wall—covered in carved magical formulas.
"It seems that even here, you haven't stopped researching," he said, leaning in to get a closer look and reading softly, "'Emotional Magic Energy Conversion and the Symbiotic Relationship with Dementors'—looks like your prison life hasn't been too bad. Maybe this place can't hold you at all?" The old man smiled and popped a fizzing sherbet into his mouth.
"Just passing the time," Sagres replied, waving his wand to erase the markings on the wall.
"Perhaps it's old age catching up with me, but lately I've been thinking… expelling you from Hogwarts five years ago might have been the greatest mistake of my life," Dumbledore said with a sigh.
Sagres frowned at those words. "Professor Dumbledore, if you've come to mock my situation, you can leave. Studying those foolish Dementors is already enough to bore me—I don't need another self-righteous visitor."
Dumbledore sighed, a trace of helplessness in his tone. "Sagres, I never intended to mock you. I expelled you back then because I believed your research had touched upon dangerous edges.. I had to think of the safety of the students at Hogwarts."
"Dangerous, huh?" Sagres shook his head. "Magic itself is dangerous." He tapped his wand on the stone bed and conjured an oak chair. "Of course, I understand your actions at the time, and I've never held a grudge against you for them."
Hearing that, the old man smiled again, pulled the chair over, and sat down. The oak seat let out a soft creak.
"I'm quite glad to hear you say that. After all, in the five years since you left Hogwarts, you haven't contacted me even once by letter."
Dumbledore's half-moon spectacles caught a faint glint of light. "I heard about your situation from Filius. I know you've never stopped seeking the true essence of magic all these years, and now you've achieved remarkable results. To be honest, I'm genuinely pleased."
"If you're here for a purpose, I suggest you speak plainly," Sagres interrupted, raising a hand. "You've done enough preamble."
"Ah, of course. What I mean is, based on your past achievements, you deserve a better research environment." As he spoke, the old man drew a wax-sealed letter from his robes. "At the same time, Hogwarts is in need of a Charms Consultant—someone to guide senior students in their theoretical research and practical work on spells, teaching all those who've passed their O.W.L.s."
Sagres took the letter but didn't open it. His fingertips brushed over the Hogwarts crest on the seal as he murmured, "Return to Hogwarts?"
His thoughts wandered, and memories of his time as a student at Hogwarts surfaced. Truthfully, that had been a "peaceful" and "wonderful" time.
Dumbledore didn't press him.
After a while, Sagres returned to the present. "I think I can accept. But Professor, this will require you to use your position as a Wizengamot adjudicator to allow me to leave here legitimately."
"Of course. I'll handle all of that," Dumbledore said, rising to his feet. "The Ministry will deliver your pardon order first thing tomorrow morning. Besides that, Sagres…"
"Afternoon tea every Thursday in the Headmaster's office, and…" He paused briefly. "When the castle needs it—protect it in your own way."
The cell fell briefly silent, the only sound the crashing of the North Sea filtering in through the iron window.
Sagres walked to the stone table and tapped the bag of lemon sherbets with his wand. The sweets arranged themselves into a miniature model of Hogwarts Castle.
"I can agree to that, Professor Dumbledore." The sugar-crafted towers gleamed translucent under the moonlight. "But I have two conditions."
"Go on."
"First, my research is not to be interfered with by any so-called Ethics Review Committee." With a flick of his wand, the candy model of the castle collapsed with a crash and reassembled into a complex three-dimensional rune structure.
"Second, when I deem certain 'traditional wisdoms' to be obstructing the truth, I reserve the right to initiate educational reform."
Dumbledore gazed at the floating sugar rune structure—it was a form of ancient Norse rune magic.
He remained silent for a long moment, then calmly extended his hand. "Then welcome to Hogwarts, Professor Greengrass."
Sagres smiled and extended his right hand as well. "This time, wandering into the Restricted Section of the library won't be a violation of school rules."
"Indeed, but please don't replace the index page of Moste Potente Potions again," Dumbledore said, blinking. "Madam Pince still believes it was a misfile on her part..."
As he watched Dumbledore disappear via Phoenix Apparition, flashes of memories that didn't belong to this world occasionally surfaced in Sagres's mind: glass beakers in a laboratory from another universe, chalkboards covered in formulas, endless experiments.
But those scenes were always swiftly pushed aside by reality—the look of disgust from his family in childhood, his mother's screams... the Cruciatus Curse... and the cold silhouette of his father walking away...
As a transmigrator, Sagres had once felt pleased with his setup at the start. After all, most people who received a transmigration script ended up as orphans with dead parents, while he had both parents alive and came from one of the Sacred Twenty-Eight—the Greengrass family.
In his initial vision, as a noble of the wizarding world, he imagined he would at least live a life free from want, enjoying the wonders of magic in a leisurely, carefree manner—perhaps even setting up a hedge fund to short Gringotts or something similar.
Let these old fossils of the magical world experience what was called "Muggle ingenuity," and properly fulfill a sense of personal value.
But reality had quickly dealt him a heavy blow.
From the moment he transmigrated to this world up until before he entered Hogwarts, the British wizarding world had been shrouded in Voldemort's rule.
That's right—he knew Voldemort would eventually be defeated, but at that time, the Dark Lord was still very much in power, and the Boy Who Lived was still in his mother's womb.
Most importantly, all he knew was that Harry Potter would be the savior, Voldemort the great villain, and that Harry would ultimately defeat him.
But as for when or how that would happen, he had no idea.
And the Greengrass family, as die-hard supporters of Voldemort, was made up almost entirely of Death Eaters.
His father was a silent and taciturn Unspeakable in the Ministry of Magic, and his mother was a Muggle-born witch.
Yes—Sagres was a half-blood.
Though his mother was a beautiful Muggle-born witch, she deeply despised Sagres's half-blood lineage.
She made no effort to conceal her hostility toward him, as if by doing so, others would forget that she herself wasn't pure-blood.
If it had only been the hatred and abuse from his family, that might have been tolerable. But later, the Greengrass Death Eaters, in order to demonstrate their loyalty to Voldemort's pure-blood ideology, actually used Sagres's mother as a sacrificial offering.
That pitiful woman, once devoted to and supportive of the Death Eaters, was tortured into madness with the Cruciatus Curse by the very people she revered—and then finished off with a Killing Curse. Just like that, her life came to a hasty, meaningless end.
When Sagres learned of this, he didn't even know whether he should feel happy or sad. Because aside from giving him life, that so-called mother had given him nothing but endless curses and torment.
At the time, five-year-old Sagres had just experienced the first magical outburst of his life. He didn't even own a wand yet, but he was already forced to confront his reality.
The thing he muttered most often back then was: "This is worse than being an orphan!"
He had no choice. The threat of death left him with only one path—to seek help from magic. And so, at the mere age of five, Sagres, backed into a corner, ended up creating the first spell of his life.
Yes, after that initial outburst of magic, he discovered his own golden finger—when the magic within his body accumulated to a certain threshold, he could forcibly improve or even create spells from nothing.
Enhanced Confundus Charm—this modified version had no offensive power, but it could make people subconsciously ignore his presence. For someone who was already invisible in his own family, it was the perfect fit.
Using this charm, he hid himself and lived on edge in that household for six years. In all honesty, it was nothing short of a miracle.
Later, he received his Hogwarts letter. On the eve of his departure, he personally sent two Death Eater relatives—who had once cast the Cruciatus Curse on him—to Azkaban.
As for his father, he had already been sentenced to prison when Voldemort fell—most likely already dead by now, kissed by a Dementor...
Flap, flap—a raven landing at the window broke his train of thought.
Sagres took the scrap of Dementor cloak from the bird's beak. With a tap of his wand, the fragment turned to ash, and a wisp of ghostly blue energy flowed into his body.
The flame-shaped rune scar on his wrist glimmered faintly under the moonlight—a souvenir from a dark magic experiment, and the very reason he could walk through Azkaban unafraid.
"It's time to leave."
Chapter 2 - Dangerous Genius
The plaque reading No. 93, Diagon Alley was nailed to a mold-speckled brick wall, and most passing wizards took it for an abandoned storage shed.
Sargeras tapped the wall three times with his wand, and the bricks rippled and reshaped like piano keys being pressed, revealing a spiral staircase leading down into the cellar. This was his temporary lodging, leased weekly for two Galleons—formerly a candy cellar beneath what used to be a sweets shop.
" Scourgify ," he murmured, flicking his wand at the oak barrels crusted over with old frosting. With the rich scent of aged cream lingering in the air, a dozen barrels rolled into place and locked together to form a desk, while the caramel syrup congealed on the wall melted into the warm amber glow of a desk lamp.
The Daily Prophet slid in through a crack in the window just as he sat down, the front page splashed with a bold headline: "Order of Merlin Medalist Cleared of All Charges, Appointed to Teach at Hogwarts." The photograph showed him from behind, his black robes whipping in the sea breeze as he stepped out of Azkaban.
Tucked just below the headline was a printed copy of the Ministry's official pardon.
Sargeras folded the newspaper into an origami crane and tossed it into the fireplace. Flames licked across the word "Dangerous Genius " as it burned, reducing the headline to ash in the blink of an eye.
Suddenly, a warm splat of bird droppings landed squarely on the pardon.
"You're two minutes and seventeen seconds late," he said flatly, without even glancing up.
Soot rained gently from the chimney as the raven Noctis landed, folding its wings with a metallic shimmer. It held a letter in its beak, the wax seal still perfectly intact.
This creature was a cursed construct he'd scavenged from the ruins of Durmstrang. Its creator had embedded a shard of obsidian into its left eye that could refract magic. Now it drew sustenance from Sargeras's magic, and in return, the raven named Noctis served as his personal courier.
Sargeras plucked the letter and skimmed it, and without a word, a quill and sheet of parchment flew out from the dragon-hide trunk nearby.
He retrieved a small pouch of mithril flakes, and Noctis immediately fluttered down onto his arm, tilting its head and letting out a sharp, piercing screech.
"Quiet…"
Silenced, the reprimanded raven turned away and began pecking at the mithril flakes. At the same time the quill scratched smoothly across the parchment:
Required Reading for Advanced Spellcraft:
Theory and Practice
Advanced Applications of Spellwork– Miranda Goshawk (Revised 1897 Edition)
Introduction to Magical Theory– the Ancient Runes Society
Topological Studies in High-Order Magical Currents– Zagreus Greengrass (Manuscript Facsimile Edition)
The quill paused briefly, then added one final line in small script at the bottom:
Recommended Materials:
Mithril-Plated Slide Rule
Dual-Sided Crystal Prism
As he finished and corked the ink bottle, sunlight was just beginning to filter through the narrow window of the cellar, casting a soft glow across his profile.
Sargeras loosened the collar of his shirt and stepped before the dressing mirror. The Hogwarts professor's black robes adjusted themselves to his form with a gentle ripple of fabric, until the silver-threaded embroidery of the Ravenclaw crest shimmered to life on the left side of his chest.
It was a privilege reserved for him as an alumnus.
---
The thick scent of coal and steam greeted him as he stepped onto Platform Nine and Three-Quarters.
Sargeras moved through the milling crowd of first-years struggling with their luggage carts, his black robes brushing the corner of a suitcase belonging to a red-haired boy—where the edge of a Chocolate Frog card peeked out, the portrait of Dumbledore winking directly at him.
"Outta the way! Make room! This stupid trunk's about to fall apart!"
Ron Weasley's shout rang out just as the lid of his trunk burst open with a loud sproing of snapping springs.
A chaotic mess of spellbooks, magazines, comic books, newspapers, a half-eaten bag of Bertie Bott's Every Flavour Beans, and even a limping old rat shot through the air, skimming past Sargeras's boots. Behind him, another bespectacled boy scrambled to tape the broken trunk back together.
"Reparo," Sargeras murmured with a flick of his hand.
The scattered items flew back into the suitcase with twice the speed, and with a metallic clink, the old brass latches reassembled themselves into a sturdier, geometric lock.
Ron gaped, and staring wide-eyed at the fully restored trunk. Before he could speak, Sargeras asked, "Red hair? Are you from the Weasley family?"
His gaze lingered briefly on the battered wand poking out of the boy's robe pocket—cheap willow, with a thin fracture running down its side. The faint glow at its tip suggested the unicorn hair core had long since frayed and begun to peek through.
Without waiting for Ron to answer, Sargeras went on, "Even if you're a first-year, not knowing the most basic repair charm is inexcusable. Especially since you're a Weasley."
The two boys just stood there, rooted to the spot, speechless and dumbfounded. Shaking his head, Sargeras turned and walked toward the end of the train.
The shrill blast of the whistle swallowed their stammered thanks.
Once he stepped into the final carriage compartment, a sheen of frost instantly spread across the door handle. A powerful repelling charm shimmered invisibly in the air, nudging the minds of any passerby to simply overlook the space.
---
Hermione Granger slid open the door to another compartment. "Have you seen a toad? Neville's lost one."
Harry and Ron, both in the middle of snacking, looked up and shook their heads at the girl standing at the compartment door. Just then, a gust of wind from the window blew open a copy of the Daily Prophet, revealing its bold front-page headline:
"Order of Merlin Medalist Cleared of All Charges! Controversial Genius Returns to Hogwarts"
The accompanying photo showed a strikingly handsome man in black robes, his profile sharp and cold like carved stone. Behind him, the iron bars of Azkaban twisted into a blurred backdrop under the morning light.
"Merlin's beard! That guy's actually going to be a professor at Hogwarts!" Ron leaned in so close his nose nearly touched the page, crumbs of Chocolate Frog smeared on the edge of the headline. "It says here he blew up five wizards with magic!"
Harry also leaned in to take a closer look, just in time to see the man in the photo suddenly lift his head and glance straight at the camera. A flash of silver flickered in those grey eyes, startling Harry so much he jerked back—his Chocolate Frog leapt straight into Ron's pumpkin juice.
"They were five Dark wizards," Hermione corrected immediately, turning to shut the compartment door behind her. "I've read several articles about him."
"What's the Order of Merlin?" Harry took the chance to ask, while Hermione tapped her wand to clean the spilled juice.
"I saw reports in more than one paper. The Daily Prophet always likes to twist things. But if you check the Department of Magical Law Enforcement archives, it clearly states that the wizards he killed were Death Eaters attempting to kidnap Muggle politicians. At the time, Professor Greengrass was a rookie in the Auror Command Division."
"But it says here he reduced their bodies to ashes…" Ron shivered a little.
"That's not fire. It was a spell he invented himself," Hermione said, pointing to a small line in the article. "'Eyewitnesses say he used only a single spell. He didn't even speak an incantation.'"
"You still haven't told me—what exactly is the Order of Merlin?" Harry pressed again, unable to hold back since neither of them had answered his question.
Hermione gave him a startled look. "You seriously don't know? The Order of Merlin is one of the highest honors in the wizarding world. It's awarded by the Wizengamot, and it's been around since the fifteenth century. It recognizes a wizard's individual achievements and contributions."
She lifted the newspaper slightly in her hands as she spoke. "It says here that on the very day he was expelled from Hogwarts, he improved several healing spells—Episkey, Vulnera Sanentur, and Rennervate among them. His improvements increased success rates on critical injuries by over sixty percent. A lot of media outlets condemned Dumbledore at the time, saying he'd gone senile for expelling someone like that."
"That kind of sounds like he was trying to prove a point to whoever kicked him out…" Harry muttered under his breath.
"I've heard my dad talk about it too. Apparently, Professor Greengrass didn't even show up to the award ceremony afterward," Ron added.
Hermione didn't respond—she neither confirmed nor denied it—but pointed to another paragraph. "It says here that after being expelled in his fifth year, he went on to study at Durmstrang and graduated two years later. He was invited to teach at Ilvermorny not long after, and resigned a year later. Then he travelled for a year. After that, the British Ministry of Magic gave him a direct appointment."
Ron, chewing on his Drooble's Best Blowing Gum, mumbled, "So in the end, he still got sent to Azkaban for murder?"
"It was self-defense!" Hermione's curls bounced with her indignant tone. "The Wizards' Rights Protection Act clearly states that when Aurors encounter danger during a mission, they're allowed to use defensive force if the situation demands it."
The young girl with brown hair gave a firm little nod, more to herself than to the others. "Two pureblood families filed the charges against him. That's probably because someone they knew was among the Death Eaters he killed."
"Then why did Headmaster Dumbledore expel him in the first place?" Harry asked, unable to hold the question in any longer.
Hermione immediately fell silent. After a moment of pause, she finally said, softly, "I don't know either…"
**
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