Dealing with the troll

The four of them headed down the stairs toward the dining hall. Apart from Will, the three young wizards all felt something was wrong. It was Halloween, yet an eerie silence filled the entire castle.

Aside from the occasional flutter of bat wings, there was barely a sound in the enormous castle. Will personally put it down to Hogwarts having excellent soundproofing. He had remembered the plot by now, too. The students from all four houses should already have returned to their dormitories.

Amid that eerie silence, Sylvia and the other two stayed close behind Will, as though afraid of encountering something terrifying. Then, as they reached the lower floors, they suddenly heard a noise from farther down the stairs.

They looked toward the sound. Below them on the spiral staircase, two young wizards were running.

"Harry, slow down! I can't keep up!" Ron panted. "Watch that staircase! It's about to move!"

Harry jumped a step, gasping for breath. Sweat had made his glasses slide halfway down his nose. "If we don't hurry, Hermione will be in danger! There's a troll in the Underground Classroom, Ron! A troll!! If you hadn't said those things, why would Hermione still be crying in the Girls’ Bathroom?"

He did have better stamina than Ron, perhaps from all the time he had spent being chased and beaten by Dudley and his friends as a child.

Higher up the spiral staircase, the four exchanged glances.

"There's a troll in the Underground Classroom? And they're going to rescue me?" Hermione was sharp enough to work it out almost immediately. Though she had no idea where the troll had come from, it was easy to see that those two still thought she was crying in the Girls’ Bathroom and were on their way to save her.

"Forget them. Let's go straight to the dining hall." Sylvia linked arms with Hermione, looking determined to stand up for her friend. "Let those two idiots spend Halloween with the troll."

"B-but that's a troll!" Neville looked as though he had remembered something horrifying. "Trolls eat children!"

"Trolls are magical creatures with an XXXX classification, though I can't understand what's so magical about them. They're described as fearsome creatures, standing twelve feet tall and weighing a tonne. Powerful, stupid, and unpredictable, with violent tendencies." Hermione certainly lived up to her reputation as a walking encyclopedia, reciting the troll's description from memory.

If Will remembered correctly, that passage came from Fantastic Beasts and Where to Find Them.

"Oh no, they'll be smashed into Halloween meat patties!" Hermione said anxiously. "We have to warn them."

She had never been a hardhearted young witch. She simply hid her fear of falling behind beneath an air of arrogance.

"You're right, Hermione! I have to warn Harry." Neville grew worried too. While he and Ron were only ordinary friends, Harry had always looked out for him. He had even clashed with Malfoy during class over Neville's Remembrall.

Hermione pulled her arm free of Sylvia's and ran downstairs with Neville.

"Hermione!" Sylvia called worriedly.

Will shrugged and pulled Sylvia along. "Come on. You don't really want to watch those two get pounded into Halloween meat patties, do you? We'd have to scrape them up afterward."

"Eww..." Whatever Sylvia had imagined made her shudder, and she followed the other two with Will.

By the time they reached the underground corridor, Will saw Harry and Ron sprinting toward them, with a troll chasing after them, a huge club in hand. Harry and Ron weren't slow, but one stride from the troll covered several of theirs. It smashed away as it moved, leaving the entire corridor in ruins, much like someone chasing cockroaches around their home.

Except that the "cockroach" here was the wizarding world's very own Chosen One.

Over the enormous crash of the troll knocking over a suit of armor, Harry yelled at Ron to speed up.

"Ron, run faster!"

"Easy for you to say!!" Ron's face was already as red as his hair as he panted along behind Harry.

Apparently, after discovering that Hermione wasn't in the Girls’ Bathroom, the two hadn't foolishly tried to fight the troll. The troll, however, apparently had no intention of letting them go.

"That's Hermione!" Harry suddenly spotted Hermione and Neville running down to the foot of the stairs. "And Neville!"

"Run! Both of you, run!" Ron felt as though his lungs were about to burst. Not only was the thing behind them fast, it stank. Worse still, Hermione, the very person he had come to rescue, was standing at the foot of the stairs, on the brink of danger again.

"Neville! Get Hermione out of here!"

Just then, Sylvia and Will came down the stairs as well, in time to hear Ron's shout.

Seeing two more people appear, Harry nearly coughed up blood in his panic. "Everyone, go back upstairs! Hurry!"

But Will seemed not to have heard him. He actually stepped in front of the others, making Harry even more frantic. Though Will was a Slytherin, Harry had never thought he was a bad person. Having also heard the rumors that Will was unpopular in Slytherin, Harry was rather well disposed toward him.

"Harry, don't forget. You're a wizard."

Then Harry thought he saw Will's silver-gray eyes flash.

Will activated [Wizard's Eye]. He could clearly see the magic within the troll, a strange sight resembling a mass of scattered, thick strands wrapped around a tiny core.

Those thick strands originated from the troll's skin. Will understood. The books said that this skin was precisely why trolls were classified as magical creatures. Skin containing this "thick-stranded magic" had extremely high magical resistance, greatly reducing the effects of spells cast on a troll.

Then I'll use magic to create a physical effect. In an instant, he decided how to deal with the troll and began moving his wand.

Harry watched Will give his wand a gentle flick. In that moment, he felt he understood a little of what Slytherins meant by "elegance."

"Aguamenti!"

With a sweep of Will's wand, a great gush of clear water erupted. A jet as thick as an arm slammed into the troll's chest, the spray instantly obscuring its tiny head. With its cocoa-bean-sized head, the troll immediately lost track of which direction to charge in, and its pace slowed.

Poor Ron, however, had been running behind Harry, and the spray soaked most of his body. It was October 31, after all. Ron, who had been sweating buckets a moment earlier, immediately began to shiver.

Still, seeing the troll held back, Harry and Ron brightened. With one last burst of effort, they reached the others, gasping for breath.

With its vision obscured, the troll swung its club wildly, smashing over the surrounding armor and statues and filling the corridor with thunderous crashes.

Seeing that the moment was right, Will stopped casting Aguamenti.

"Glacius!"

A pale blue stream of freezing air burst from the tip of Will's wand and struck the drenched troll. Within a few breaths, great sheets of ice had formed over its body.

Will paid particular attention to its head. That cocoa-bean-sized head was now encased in a thick layer of ice.

Even then, the troll remained standing, a testament to its formidable constitution.

Fortunately, it really was astonishingly stupid. As the ice made breathing increasingly difficult, the troll actually rammed its head into the corridor wall. Will saw it perfectly clearly: the tremendous force of the collision drove the troll's head almost entirely into its chest.

Then the troll collapsed onto the ice. A thin layer had frozen over almost the entire corridor.

"Hah... hah... Let's get out of here. It's... it's too dangerous." Harry still felt unbearably hot, as though every breath he exhaled carried scorching flames. Only the cold air he drew into his lungs brought him a little relief.

Beside him, Ron was shaking like a leaf, his teeth chattering. He sounded as though Quirrell had possessed him. "Y-yes... it's t-too... too cold here. L-let's... let's g-go back."

"We might have to wait a while before we can go back." Neville tugged at Will's robes.

Did Will need that tug? He had already heard the footsteps on the stairs. Turning his head, he saw Professor McGonagall at the front of the approaching group. Her face was deathly pale, but she was clearly furious—