TheFanficGOD
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CASS11- Unerasable History
🕑 Added 2025-07-18 13:07:49 +0000 UTCThe following days followed a rhythm. Every class started with Cassian flicking his wand and letting Lumos Spectaculum do the heavy lifting. The walls of his classroom came alive with battles, duels, rebellions, and ancient rituals. Students who had come expecting another dull hour of names and dates found themselves watching history move before their eyes… Merlin arguing with Arthur, goblins clashing with wizards, witches standing at the stake with smirks, untouched by the flames.
Once they were hooked, he would move on. Each lesson ended with a spell… not just recited, but dissected, stripped to its bones. Cassian made them see it, feel it, build it in their heads before even touching a wand. Wizards had been casting long before wands became fashionable, and he intended his students to know why. Half the time, Hogwarts taught students to memorise spells like a list of ingredients in a potions book. Cassian wanted them to understand what they were doing. He didn't want parrots mumbling Latin. He wanted them to understand… because Magicks who understood were Magicks who survived.
And it worked.
By the end of the first week, History of Magic had stopped being the school's designated nap time. Now, students actually looked forward to it. Even the ones who usually coasted through lectures sat up when the lights dimmed and Cassian let history unfold in glowing illusions. Slytherins, Gryffindors, Ravenclaws, Hufflepuffs… it didn't matter. No one liked missing class when they would be the only one who didn't see Charlemagne duel a rogue alchemist or a medieval wizard set fire to an entire castle with a single curse.
Of course, not everyone got to have fun. First-years weren't ready to be playing with fire yet… quite literally. Cassian made that clear on their first day. He wasn't their Charms professor, nor was he in charge of Defence Against the Dark Arts. That responsibility fell to Flitwick and Mulford, who would, in due time, teach them the proper way to handle magic without losing an eyebrow… or worse.
He told them as much, leaning against his desk as a few eager Gryffindors bounced in their seats, clearly hoping for something more exciting than history. "You lot are stuck with me for storytelling, not spellwork," he said, eyeing a particularly restless Fred and George Weasley. "I will leave the explosions to Professor Flitwick and the duelling to Professor Mulford. They get paid to make sure you don't accidentally set yourselves on fire or hex your own limbs off. I, on the other hand, don't have the patience to deal with screaming first-years running around with burnt fingers."
A few chuckles rippled through the class, but Cassian didn't budge on it. First-years weren't ready for practical spellwork beyond the basics, and that was something their actual spellcasting professors would ease them into. Until then, they would stick to history… though if they behaved, he might throw in a few illusions now and then to keep them entertained. He wasn't heartless. Just realistic.
But for the rest, Cassian introduced Incendio, the Fire-Making Charm. Six classes, four houses, hundreds of students… all given a crash course in the spell's history, application, and the reality that magic worked best when you actually understood what you were doing. The result? Another reward from the system. Incendio… Maximum Mastery. And, because things apparently weren't weird enough already, two more ancient variations landed in his lap.
Cassian sat in his quarters that evening, staring at the updated list floating in his mind.
Fire-Making Spell (Incendio)
Ancient Variant: Cinis Amissa - Instead of creating fire, this spell summons the ash of a past flame. The caster sees what was last burned in that location. Can reveal destroyed books, lost scrolls, or hidden evidence of magical crimes.
Fire-Making Spell (Incendio)
Ancient Variant: Pyroclave - Unlike modern fire spells that create fire instantly, Pyroclave is a delayed fire release spell that stores flames inside objects, runes, or written texts, only to be unleashed under specific conditions.
Cassian narrowed his eyes at the first one. Cinis Amissa. It wasn't just a spell for summoning ash… it forced fire to give up its secrets. The ashes of whatever was burned would retain the memory of what they once were, revealing hidden truths long thought lost. That kind of magic wasn't just old… it was dangerous.
His vision blurred as something pulled at the edges of his mind, dragging him somewhere else. He let it take him.
A dark alley. Wet stone glistening under the dim glow of a wand. A hooded figure moving quickly, stacks of books piled on a crate. He flipped through pages in frantic desperation before tossing them into a conjured fire. Flames swallowed parchment, curling ink into smoke. Whatever was written there… gone.
Days later, a different person stood in the same alley. Hood drawn, wand raised. "Cinis Amissa." The ashes, long settled into filth and rainwater, glowed red. Slowly, they lifted, reforming… not whole, but enough. Pages, ghostly in their incompleteness, hovered in the air. Letters seared back into existence.
The wizard's breath hitched. A name. A date. A crime long buried.
And then… voices. Echoes of the past, trapped in the ash. Whispers, then shouts. The crackle of fire. A curse muttered just before the books burned. The wizard staggered back. Cinis Amissa didn't just summon ash… it rewound destruction, let the past bleed back into the present. A wizard could stand in a burned-down library and see every page that had turned to cinders, hear voices that had long since gone silent.
Or, in the wrong hands, erase the evidence entirely.
The vision snapped out like a flame smothered by wind. Cassian inhaled sharply, fingers tightening around his wand. Of course it had been banned. Magic like this didn't preserve history… it weaponised it. If criminals used fire to erase magical evidence, it meant entire histories could be rewritten. But those who knew the spell could unwrite the rewriting.
His gaze flicked back to the list.
Pyroclave.
Again, his vision shifted.
A master runesmith in a dimly lit workshop, his hands steady as he carved words into stone. Each letter glowed as he whispered the spell. "Pyroclave." The light faded, the inscription vanishing before his eyes. To anyone else, the stone was blank. But the fire was there, waiting.
Centuries passed. A thief, careless and greedy, stumbled into the abandoned ruins. His fingers traced over the old stone, rubbing at the surface as if searching for treasure.
The moment his palm rested fully against the inscription, it ignited. Fire roared to life from the once-invisible words, consuming him in a flash of heat and screaming embers.
Later, the runesmith's apprentices stood before the charred remains of their master's workshop. The knowledge was too dangerous, they agreed. It had to be destroyed. One by one, they set fire to the scrolls detailing Pyroclave, swearing the spell would die with them.
Magic designed to last. Magic that carried intent across generations.
Cassian rested his head against the back of his chair, staring at the ceiling.
What was he supposed to do with this?
He could feel it in his wand… The knowledge pressed at his skull, like fire caged under glass, humming for release. If he tested them, it would be easy. A whisper, a flick of his wrist, and history would crack open.
But this wasn't some new variation of Incendio, something a third-year could manage after a few tries. This was buried knowledge, and for good reason.
These weren't just lost spells. They were remnants of something older than Hogwarts itself, magic that had shaped history before history was recorded. And now, for whatever reason, they were resurfacing.
His grip on his wand loosened.
Interesting.
---
Cassian stepped into the Headmaster's office, greeted by the sight of four House Heads already seated. Dumbledore sat at his desk, fingers steepled, while McGonagall, Sprout, Flitwick, and Snape occupied their usual spots.
"Professor Rosier," Dumbledore greeted, eyes twinkling in that unreadable way of his. "I trust your first few weeks have been… enlightening?"
Cassian folded his arms. "That is one way to put it."
McGonagall adjusted her spectacles. "I believe 'revolutionary' would be more accurate. I've had no fewer than twenty students tell me that History of Magic is now their favourite subject."
Flitwick beamed. "Quite right! I've seen students practicing spells from your lessons in the corridors… not in an unsafe manner, of course, but with genuine enthusiasm."
Sprout nodded. "My Hufflepuffs haven't stopped talking about it. Even the ones who never cared for history before."
Snape exhaled sharply through his nose. "Yes, quite the marvel. Teaching history through elaborate illusions and… correct me if I am mistaken, practical spellwork." His tone dripped with disapproval. "I wasn't aware the Board had hired a history professor to moonlight as a Charms and Defence instructor. Shall we all start treading on each other's subjects?"
Cassian didn't blink. "God forbid we make history interesting. Next thing you know, students might start thinking for themselves."
McGonagall cut in before Snape could fire back. "The issue, Professor Rosier, is that your methods, while undeniably effective… blur the lines between subjects. First-years expect spellwork in their History classes, and while I appreciate your enthusiasm, it does complicate matters."
Cassian offered an easy smile. "I assure you all, my intention is to teach and nothing more. I know my appointment here isn't exactly based on merit, and I understand the concerns that might raise. But I take my responsibilities seriously."
McGonagall studied him over the rim of her glasses. "That much is clear."
Sprout nodded. "More than clear. You've managed to make a subject students usually sleep through into something they actually talk about outside of class. I hear about your lessons in my greenhouses more than I do about actual Herbology."
Flitwick chuckled. "A rather impressive feat, I must say. Not only engaging but quite… illuminating, from what I gather."
Snape exhaled sharply through his nose. "Yes, truly groundbreaking. I imagine Flitwick and Mulford are thrilled to have a History professor who fancies himself a Charms and Defence instructor as well."
Cassian didn't bother looking at him. "I don't teach them spells beyond what they should already know. I simply ensure they understand where those spells come from, how they evolved, and why they mattered in history. They don't leave my classroom with anything they wouldn't have learned eventually."
Snape's lip curled slightly, but Dumbledore cut in before he could say more. "Professor Rosier, would you mind giving us a demonstration? I admit, I am rather curious myself."
Cassian leaned back in his chair. "Any requests?"
Dumbledore's smile deepened. "Surprise us, Professor Rosier. That does seem to be your speciality."
Comments
TheFanficGOD
Me and some of my pals have actually been discussing Harry Potter for years, plot holes (there are tons), weird little details, and all the interesting stuff. Plus, I used to read loads of fanfics. Most of my takes come straight from all that.
Tungst3n
Glad to see magic used in a practical sense, to many fic's just stick to the story and dont explore the magical world.
BraveHeart
Your explanations for the history of the HP world and how he teaches are amazing I must say
