Third-Floor Corridor.
The training ground originally meant for Defense Against the Dark Arts practicals had been transformed into... an industrial-style arena?
The floor was paved with fireproof tiles, high-pressure water cannons were set up on all four sides, and an automatic sprinkler system was installed on the ceiling.
Ivan stood in the center of the arena, holding an alchemically modified megaphone, directing a group of house-elves wearing orange reflective vests as they debugged the equipment.
"Hey you, Dobby! Adjust the water pressure to Level 3! Don't blast Mr. Grindelwald downstairs!"
"And you, Winky! Are the foam extinguishers ready? I want the strawberry-scented ones!"
Opposite him.
Gellert Grindelwald stood in his signature black robes, gripping the Elder Wand tight, his face livid.
He felt like he wasn't here for a duel, but for some farce.
"Potter!" Grindelwald roared, unable to bear it anymore. "This is your exam site? This is your defensive art? A bunch of house-elves holding water hoses?"
"Don't be impatient, Gellert." Ivan checked his watch. "This is called 'Targeted Defense'. Doesn't your Fiendfyre claim to 'burn everything'? My system specializes in curing all kinds of defiance."
By now, the stands were packed.
Dumbledore, Snape, McGonagall, even Hagrid holding a Blast-Ended Skrewt, and a nervous Minister Fudge were all present.
"Dumbledore," Fudge wiped his sweat, asking quietly, "Isn't... isn't this too reckless? Letting students play with water? What if it gets out of control?"
Dumbledore was happily chewing on a Bertie Bott's Every Flavour Bean, mumbling indistinctly, "Oh, don't worry, Cornelius. Ivan calls this a 'Stress Test'. Besides, I find that strawberry extinguisher quite interesting."
Snape sat in the shadows, commenting coldly, "If that kid connected the hoses to the Potions classroom's water supply, I'll boil him into a pot of slugs."
Though he said this, his eyes were locked onto the hose connectors—Ivan's newly invented "Hydro-Drive Spell Amplifiers." Snape really wanted to steal the tech and modify it into an automatic cauldron washer.
"Exam start!"
Professor McGonagall blew the whistle.
Killing intent instantly exploded in Grindelwald's eyes.
Since you want to play with water, I'll evaporate it all!
"Fiendfyre!"
BOOM—!!
Terrifying black flames erupted instantly from the tip of Grindelwald's wand, transforming into a massive fire serpent charging toward Ivan with the intent to destroy everything.
The surrounding air twisted instantly from the high heat, and students in the stands screamed in terror.
"Merlin! That's Fiendfyre! It devours everything!" Ron scrambled under a table.
Hermione clutched her notebook tight, snapping her quill tip. "Ivan! Use the counter-curse! That's Fiendfyre!"
However, Ivan stood there without even raising his wand.
He simply snapped his fingers.
"Activate: Level 1 Response Protocol."
In the next second.
HISSS——————!!
Over a dozen high-pressure water jets shot out simultaneously from all directions, converging precisely in mid-air to form a massive water net that directly enveloped the fire serpent.
Sizzle sizzle sizzle—!
Steam instantly filled the entire arena.
The originally ferocious Fiendfyre serpent didn't even have time to wail. Like a snake pinched at its weak point (seven inches), it instantly withered, extinguished, and finally turned into a puddle of black, smoking muddy water.
Dead silence.
Grindelwald held his wand, frozen in his casting pose, completely petrified.
His Fiendfyre... was squirted out by water?
This isn't magical! This isn't scientific!
"This... this is impossible!" Grindelwald shouted, losing his composure. "Fiendfyre is magical fire! Water can't extinguish it! Unless it's Devil's Fire... no, that's not right!"
"Who told you I used just water?" Ivan pulled a bottle of bubbling green liquid from his pocket and tossed it to Dobby. "Add 'Foam Inhibitor', it's dish soap plus modified potion, specifically designed to break the surface tension of flames. Didn't your physics teacher teach you? Cutting off oxygen puts out fire."
Dobby caught the bottle, screaming excitedly, "Dobby likes putting out fires! Dobby is a Firefighter Elf!"
He poured the liquid into the console's tank.
Puff puff puff!
This time, what sprayed out wasn't water, but a sky-filling white foam, burying the dazed Grindelwald like an avalanche.
"Cough cough cough! Potter! This is cheating!" Grindelwald struggled in the foam like a fly trapped in cream. "This is despicable! This isn't a Dark Magic duel!"
Ivan sighed, walked to the foam pile, and pointed his wand.
"Evanesco."
The foam vanished instantly.
Grindelwald stood there looking wretched. A slipper hung from his hair (thrown by some inaccurate elf), and his handsome black robes were plastered wetly to his body like a drowned rat.
"Gellert," Ivan patted his shoulder, speaking earnestly, "times have changed. Modern Dark Magic emphasizes 'Attribute Countering'. Your Fiendfyre is Fire element, my water gun is Water element; I naturally counter you. Just like in a game, if you meet a meta hero, you have to admit defeat if you can't beat them."
> [System Alert: Grindelwald (Worldview Shattered + Humiliation Rage + Confusion over "Physical Firefighting"): Emotion Value +999!]
On the Stands.
Professor McGonagall's mouth was wide enough to fit a pumpkin.
"Is... is it over?" She looked at Snape. "Severus, does this meet the grading criteria?"
The corner of Snape's mouth twitched slightly, as if suppressing laughter. "Although the method... was a bit crude. But looking at the result, he indeed 'defended' against Fiendfyre and 'counterattacked' the opponent. According to the 'Result-Oriented' principle..."
He took a deep breath and announced loudly: "Fifty points to Slytherin! For Ivan Potter demonstrating 'Innovative Thinking in High-Efficiency Firefighting'!"
"YEAH!!"
Slytherin students cheered.
Gryffindor students looked at each other.
Harry looked at Grindelwald, who had been sprayed into submission by water guns, and suddenly felt his Nimbus 2000 wasn't so appealing anymore.
"Wait!" Grindelwald wasn't giving up. He wiped water from his face, gritting his teeth. "That was just defense! What about offense? If I surround the whole arena with Fiendfyre, can your hoses save you?"
Ivan looked at him like he was an elementary student who hadn't finished homework.
"Gellert, why do you think I'd give you the chance to surround the arena?"
Ivan pointed at the ceiling.
Grindelwald instinctively looked up.
The ceiling was covered in dense... copper pipes?
No, those were alchemically modified "Thundercloud Generators."
"Since it's an exam, let's do the full set." Ivan snapped his fingers. "Thunder King Mode, Activate. Voltage: Low Safety Setting (don't want to electrocute you to death)."
Crack!
A blue electric arc only as thick as a finger struck precisely into the puddle by Grindelwald's feet.
Zap!
Grindelwald's dazzling blonde hair stood up instantly, turning into a standard afro, smoking slightly.
"Is... is this a Weather Charm?" Grindelwald asked tremblingly, hair singed.
"No," Ivan smiled slightly. "This is Tesla Coil principles plus Thunderbird feather core. How about it? Want to try 'Artificial Rain'? I can make you a rainbow."
Grindelwald looked at the sparking puddle, then at Ivan's "I have a hundred other ways to play" face.
His proud Dark Magic seemed like child's play in the opponent's hands.
"I..." Grindelwald opened his mouth, but finally lowered his wand dejectedly.
But the light in his eyes didn't extinguish; it burned brighter.
It was the excitement of finding prey.
"You win, Potter." Grindelwald squeezed the words through his teeth. "But this is just the beginning. One day, I will use your 'Science' to rule your 'World'."
Ivan shrugged indifferently. "Welcome anytime. But remember to book in advance next time; my appearance fee is expensive."
Just then, Dumbledore, who had been watching the show, stood up.
He clapped his hands, drawing everyone's attention.
"Brilliant! Absolutely brilliant!" The Old Bee smiled until his eyes were slits. "I declare, for this semester's Defense Against the Dark Arts final exam, Ivan Potter—Full Marks!"
"Wait!" Professor McGonagall suddenly stood up, holding a roll of parchment—the essay Ivan casually wrote earlier. "Headmaster, you haven't seen this! This is the essay Ivan wrote during the exam... 'On the Application of Quantum Mechanics in Transfiguration — A Case Study of Automatic Quills'!"
McGonagall's voice trembled with excitement.
"This... this is a genius concept! According to this theory, we can create 'Transfigured Creatures that Grade Homework Automatically'! Think of how much professor labor this will liberate!"
She turned to look at Ivan like he was a rare treasure. "Ivan, can this paper... be published? Can I add my name? Even as second author is fine!"
Ivan was drinking water and almost choked. "Professor, calm down. As long as you don't deduct points from Slytherin, the paper is yours."
"No deductions! Absolutely no deductions!" McGonagall hugged the paper tight, afraid Snape might snatch it. "Whoever dares deduct Ivan's points, I'll turn them into an automatic quill!"
Snape: ???
I want that paper too!
Minister Fudge watched this, feeling his worldview restructuring.
That terrifying Defense Against the Dark Arts exam turned into a tech launch event?
The feared Grindelwald became Ivan's background board?
"Um... Headmaster Dumbledore," Fudge raised his hand cautiously. "Since the exam is over, about Student Ivan... that 'cross-dressing' bet..."
The hall went silent instantly.
Everyone's eyes focused on Grindelwald.
Grindelwald's face turned liver-colored.
He remembered the pink, lace-trimmed Lolita dress.
"I..." Grindelwald took a deep breath. As a future Dark Lord, honoring a bet was basic integrity. "I will fulfill my promise. BUT!"
He stared dead at Ivan. "Potter, don't celebrate too early. If you lose, you have to wear one too!"
"Relax. Not only will I wear one, I'll prepare a set for you too."
Ivan clapped his hands.
Dobby walked out holding two exquisite gift boxes.
"Since it's a duet," Ivan opened one box, revealing an extremely dashing black and gold tailcoat. "To match your blonde hair, I specially made this 'Magically Modified Butler Suit'. As for me..."
Ivan took out the other one.
It wasn't the pink Lolita dress.
It was a pure white, diamond-encrusted, gorgeous gown that looked like a wedding dress.
But the hem was styled like a combat uniform, and a Slytherin green cape hung from the back.
"This is called 'Haute Couture Battle Damage Style'." Ivan shook the dress out, the glittering sequins nearly blinding Fudge. "How about it? Isn't this much classier than your lace dress?"
Grindelwald looked at the dashing tailcoat, then at the domineering "Battle Dress" in Ivan's hand.
He had to admit... this suited his taste.
"Hmph." Grindelwald turned his head away, but the corner of his mouth couldn't help curving up. "Barely worthy of my status."
Dumbledore laughed on the stands like a two-hundred-pound child.
"My, it seems this year's Halloween Ball will be very interesting. Severus, go get my camera; I want to record the whole thing."
Snape stood up expressionlessly. "I'll get the invisible camera. Also, Ivan, about your 'Automatic Cauldron Washer'... really not considering a patent?"