Hermione was very angry with Harry, of all people, right after Ron's adventure with the duel, portals, and giant wolf. She'd stayed up to try to talk Ron and Seamus out of it, wound up getting drawn off with them, and actually been responsible for unlocking the door blocking off the convergence. And she'd initially stayed up to save Harry from making a mistake, only to learn that he'd never had any intention of going along with the stupid stunt.
But it wasn't like she was going to stop studying with the other Midgardborn, so she'd mostly forgiven him within a few weeks. Snape had been a little better in class, herbology had proved to at least be slightly interesting, and Harry had found some introductory math textbooks in the library so they wouldn't all completely lose their skills by the time they could take arithmancy class. Ron had bonded heavily with Seamus over their adventure and didn't want to do extra homework, but Neville still seemed to feel like he owed Harry for saving him at the flying lesson, so he tried to come to the study sessions. Parvati would only show up when Padma could make it, and would drag Lavender along, so the Gryffindor first-years were starting to at least get some kind of working relationship. Still, Harry, Dean, and Hermione remained the core of the study group.
Before they knew it, they'd been at school for nearly two months. The single-day weekends really had a lot to do with how little time they had to simply slack off, but Harry's study group was trying to fit in a lot of extra learning. In particular, Dean had been a bit of a slave-driver for the defense seminar, persuading them that they couldn't learn martial arts in only four hours of class time a week. He seemed to enjoy watching them all try to keep up with him on morning jogs, and laying them out with various throws on the lawn.
"Dísablót feast coming up on Frigga's Day," Lavender reminded the crew, at a study session she'd deigned to attend one week.
Hermione did the math, then figured, "Is it the same day as Halloween on Midgard? Autumn-Month 11th doesn't seem like a particularly auspicious date?"
The Vanir girl shrugged, and explained, "I think that's just when portals to Niflheim open up across all the realms. Is it on an important date on Midgard?"
"Halloween is at least at the end of a month," Harry said. "I don't know if we see any portals on Midgard."
Dean theorized, "I bet the Masters keep them secret."
Lavender explained, "It's when the ghosts here can come and go back to Niflheim. I think they have to every few years, or they'll fade."
"I wonder if Midgard even has ghosts," Hermione mused. She made a note to herself to investigate. It was probably her hundredth such note. That Harry would often help her research these questions was why she'd eventually forgiven him.
By the time the Dísablót feast came, they'd at least confirmed, in Hogwarts' giant library, that ghosts were practically unheard of on Midgard. Or, at least, they were much more difficult to corroborate than the parade of spirits that considered Hogwarts a second home. The Gryffindor crew had started getting a little blasé about the incorporeal undead, since Sir Nicholas (or "Nearly-Headless Nick") was around so often. Basically considering himself the house's immortal patron, the incompletely-decapitated Asgardian nobleman still hadn't explained what exactly he'd done to justify his execution, why he'd been sent to Niflheim, or why he was allowed to come back. But he was a nice enough weirdo who at least spoke English close enough to modern to basically puzzle out what he was saying, so the kids gave him a lot of slack.
Despite Hermione's displeasure, Harry had spent the last few weeks building up the legend of Ronald Weasley. He figured that the redheaded boy enjoyed the attention, tired of being overshadowed by older brothers, and if he could make the kid into some kind of hero, that was less he had to hear about the "boy-who-lived." In addition to his whisper campaign about how Ron had discovered the secret of the forbidden corridor after Draco Malfoy had been too cowardly to duel him, Harry had started a few other rumors. Ron Weasley had wrestled a troll to ensure his admittance to Gryffindor. He was a prodigy on a broom, cruelly forbidden from quidditch as a first-year. You know how the seventh-son of a seventh-son was automatically a powerful wizard? No Vanaheim wizarding family had more sons than the Weasleys, and Ron was the last of them.
Ron was starting to believe his own hype.
Harry had his first inkling he'd pushed the redhead too far the day before Halloween. In a rare moment of overlap, the holiday was on a Friday on Midgard, and it was always a Frigga's Day on Vanaheim. This made having an evening feast extra convenient for the castle. Fridays were relatively light for Gryffindor first-years, with only an extra-long chemistry class in the morning, and a single-period transfiguration class after lunch. But on Thursdays, they had a frantic mix of spellcasting, transfiguration, flying, and history. And Ron was being extra in all of them.
"I don't understand why we're doing levitation," the young Weasley opined, loudly, in the middle of spellcasting. "We were just starting to figure out energy projection! I want to learn to really blast someone."
"Ronald Weasley," Hermione rolled her eyes, explaining, "if you'd actually read the textbook, you'd know there's only so much energy we can project at our age. Magister Flitwick only taught us that much so we'd get used to channeling energy through our wands. Levitation is about mastering versatility."
"Ver-sa-til-i-ty," Ron mocked, stressing all the syllables of Hermione's five-dollar word. "Like levitating a feather is ever going to matter in a fight."
"Maybe a rock? Fling it at someone," Harry suggested, seeing that Hermione was doing the pinchy thing with her mouth that was a sign that she was about to go on a rant that didn't make her any friends. "I'm curious about the difference in levitation and the thing the book called 'uplift.'"
"Ah! Yes, excellent question, Mr. Potter," the diminutive professor answered, passing by their group. "The second option is not commonly used on Vanaheim, but is potentially more useful to you should you return to Midgard. Attend, class, this might be important for all of you." Once he had their attention, he continued to explain, "Most true workings at a distance involve Vanaheim's energy. You're exhorting the world to lift your object. While we're currently experimenting with a feather on your desk, this spell can target anything you can see. Sometimes, even things at a greater distance."
"But on Midgard, that requires a bargain, correct, Magister?" Hermione asked.
"Exactly, Ms. Granger," Flitwick nodded. "Since most worlds do not have their own magical field, free for the commanding, as we have here, outside Vanaheim this spell only works if backed by a Principality. The most common such entity for levitation is the dread Dormammu, who it is dangerous to treat with, though other sources such as chaos magic may also fuel it."
Dean blanched and said, "I don't think I want to call on Dormammu or chaos just to lift a feather, sir."
"Quite right," the professor nodded. "Which is why the wizards of Midgard tend to use the secondary concept, which Mr. Potter has pointed out. Your book calls it 'uplift.' This is simply making a connection between your energy and the object, and using a secondary function of the personal energy whip to bodily drag the object into the air. It's a much more limited range, and provides an obvious connection with the caster, reducing your ability to lift things stealthily."
"A tractor beam!" Parvati suggested, and the others from Midgard who'd seen Star Wars nodded.
Strangely, Flitwick seemed to get the reference, and agreed, "Close enough. Why don't we try both versions and compare their strengths and weaknesses? Remember that while you're learning a spell, it's helpful to say the mnemonic. The one for this spell is 'Girding Wings of Lofn-Odr.'"
Seamus Finnegan found out very quickly that connecting his wand to his feather on a rope of orange light was an excellent way to burn it to a crisp, but about half the class of 18 managed to tug the feather around on their magical whips like demented yo-yos. By the end of the class, only six kids were able to use the levitation spell which was the original lesson, which lifted the feather calmly in the faint turquoise glow of Vanaheim's magic. Ron was one of the few that didn't manage either method, and that made him overcompensate for the rest of their classes on Thor's Day and into Frigga's Day.
Rector McGonagall, who had him both days, finally had enough after lunch on the afternoon before the feast, "Put your wand away, Mr. Weasley," she ordered. "No one is even going to begin transfiguring their matchsticks into needles until we finish diagramming the comparative structure of wood and of steel."
"Is this still going on?" Padma whispered to Parvati. The Ravenclaws happened to have both spellcasting and transfiguration with the Gryffindors.
Parvati sighed and nodded, "He and Seamus blew up a cauldron in chemistry before lunch. Cost us twenty points. I'm worried he might start a food fight at the feast or something."
"We'll sit on the other end of the table from him, just in case," Padma suggested.
The Hogwarts Dísablót feast would be a terrible thing to ruin with a food fight (though Harry privately had an ambition to pull a Headless Horseman and peg someone with a jack-o'-lantern). In addition to the loss of all the spooky decoration, the primary reason for the feast was to use up the foodstuffs that wouldn't last the winter before switching to the more durable crops from the fall harvest. Padma and Parvati, in particular, didn't want their last access to fresh fruits and vegetables interrupted.
Harry, Hermione, Dean, and Neville looked somewhat mournfully at the other end of the table, where the Patil twins had sat far away (and consolidated most of the platters of greens) along with Lavender and some of Padma's Ravenclaw friends. Ron and Seamus weren't in danger of creating a food fight, but they were planning something even more outlandish. Ron gestured with a chicken leg as if it was his wand, "We just get in, blow up a few of the lesser draugr, grab a weapon as proof, and come right back."
Seamus seemed to be taking it seriously. "At the very least, I kin use m'energy whip an' steal one o' their swords, afore they e'en know it's a wizard they're dealin' wi'."
"Right. Versatility," he nodded at Hermione. From his tone of voice, she wasn't sure if he was finally acknowledging her point from the previous day's class or still just being a little shit about it.
Deciding to split the difference, she asked, "Can the living even go to Niflheim?" She was reasonably sure the answer was, "only in special circumstances." But maybe the annual infestation of portals counted, and nobody used them because they'd become dead very quickly if they got stuck.
"Probably," Ron said, not concerned. Realistically, unless one of the portals popped open in their dorm, he wasn't exactly going to have the opportunity to follow through with his wild plan. But he figured he would get credit for planning it. "What do you think, Harry? Coming with?"
"To Niflheim?" Harry asked, finally tuning back into the conversation. He was always in his head on Halloween. His aunt hadn't mentioned it for his first few trick or treats, but it had eventually come out that his parents had died on that night, and it hadn't been the same for him ever since. "Do all the dead go there?"
That gave most of the group a pause, and it was Neville who piped in with, "Only some of them. And you'd never find anyone you're looking for unless you're dead yourself." In a moment of insight, he suggested, "But your parents must have gone to Valhalla. They died in battle."
Suddenly everyone got it and glanced at Harry, who wiped the beginnings of a tear from his eye under his glasses. "Thanks, Nev. Yeah, I don't know if there's anything for me in Niflheim, Ron. Thanks anyway."
They had a few more sombre minutes of eating, before their defense teacher, Mistress Morgan, suddenly entered the hall and moved quickly and gracefully up to the staff table, having a hushed conversation with the headmaster. Dumbledore nodded, whispered to the rest of the teachers, and had most of the great hall's attention when he finally spoke up, "I'm sorry to cut the feast short. Prefects: please escort your charges back to their dormitories." He was going to leave it at that, but decided to add, "It seems raiding season has started a bit early. I'm certain the castle is secure, but out of an abundance of caution, we're moving you students to the safest bastions in case the staff needs to mount a defense."
"Raiding season?" Harry asked.
As everyone was getting up, Ron tried to explain, but was busy shoving the rest of his dinner into his mouth, so Neville said, "Trolls and giants and sometimes just bad people often show up places in the winter, looking for food and treasure. Don't know why they'd bother trying to get into Hogwarts."
Seated furthest from the door, they suddenly learned the answer before they were out of the hall. A tremendous metallic crashing could be heard from below, the sound of impact vibrating the stones beneath their feet. "The portcullis on the boat entrance!" Hermione guessed.
The noise turned a fairly orderly evacuation into mild chaos, which only intensified when the stout door into the lake access began to shudder, as someone on the other side attempted to batter it down. Screams spread throughout the area as most of the students began to rush out of the entry hall and toward their common rooms. Gryffindor, however, had quite a few students dither not out of fear, but because they felt like they should attempt to help fight. "Keep moving!" Percy Weasley insisted from the back of the crush. "To the stairs!"
Still bringing up the rear, Harry and his friends had only just exited the great hall into Hogwarts' enormous foyer when the lake door gave up and shattered. While it was nowhere near as big as the gigantic double doors that led in from the grounds, it was at least large enough to be comfortable for Hagrid. In fact, many of the doors in the castle were far larger than they needed to be for beings on a human scale, so wouldn't really provide a squeezing disadvantage to the raiders currently shoving their way into the school. Someone screamed, "Trolls!"
Harry wasn't sure why he'd assumed trolls would look like the CGI creatures from the Lord of the Rings movies. Instead, they looked a lot like Beast Man from the old He-Man cartoons: only a bit bigger than a tall human, bestial, hairy, and orange.
If someone told him that they were Hagrid's Weasley cousins, he'd have almost believed it.
They wore armor, wielded large and sharp-looking axes, and looked dangerously smart. As if that weren't enough, once several had charged into the room, an even larger being squeezed itself through the door and then stood to be taller than Hagrid, frozen mist evaporating off of its blue skin. "And a Jotun!" another helpful, fleeing student yelled.
While the exploding door didn't manage to hit any children, the arrival neatly broke the fleeing line of students down the middle. Everyone not closer to the stairs than the attackers began to flee around the corner and toward the ground floor classrooms. Well, some of the upper-year Gryffindors began putting up magical shields as the professors shouted spells and joined the melee. But the majority of the remaining Gryffindors and Ravenclaws (who had been sitting furthest from the door) fled.
Harry tried to stay close to his friends, but there were probably fifty students in the initial crush and he wasn't sure if different groups were splitting into different corridors up front. "Secret passage here!" he heard one of the Weasley twins offer, identifiable by his shock of red hair.
"Well, not that secret! Definitely keep moving," the other twin amended, as he waved the line of kids into a concealed tunnel that the first-years hadn't discovered yet.
The corridor clearly wound between classrooms, a narrow channel hidden in the walls that might not be obvious without a precise tape measure if you were trying to map out the used space within the floorplan. It might be plenty of space for Fred and George trying to get to class, but was a tight fit for a gaggle of fleeing children. "Trolls probably can't even fit in here, so we could just stay put," Hermione suggested.
Harry stuck his arms out until they hit the walls, estimated the distance to the ceiling that was barely visible under the light of lit wands, did some quick math, and wasn't convinced. He countered, "Want to bet your life on that?"
After juking left and then right to trace out the boundaries of the surrounding classrooms, the group began struggling up a spiral staircase with some fairly steep risers. Harry had been right about quickly developing calves of steel with all the stairs in the castle, but the angle of ascent was tiring even for trained legs. Plus, the momentary surge of adrenaline from the attack was fading with the longer travel through the relatively safe tunnel, and the students were starting to feel their full bellies and the nearness of bedtime.
Finally, the staircase ended. One of the twins said, "Third floor. Lets out near the girls' toilets."
The other added, "Fastest way is to get back on the main stairs."
"Form an orderly queue," Percy Weasley ordered from the back. Harry was surprised that the officious prefect had managed to stay with them, but he didn't seem to be willing to abandon his charges.
"The main stairs aren't the fastest for us," Cho Chang argued. Harry hadn't even realized that Wong's cousin had been in the crush with them.
Alexis Marie, the other fifth-year Gryffindor prefect, said, "I'll take the Ravenclaws?"
"Be safe," Percy agreed, then led his own charges toward the large central stairwell that rose through the middle of the castle. As they got closer, they could begin to make out the sound of yelling and spellfire below. "They will be fine," the prefect said, almost as if to convince himself. "Trolls are simply very durable and somewhat magic resistant, and they regenerate, so they will take time to fully put down."
In the larger corridor on the third floor, they were finally able to count exactly who they had with them. Fifteen in total, they were made up of all five boys from the Gryffindor first-years, Hermione, all of the older Weasley boys and their friend Lee, and five second or third-years that Harry hadn't really talked to much yet. "This is stupid. We should have just gone with the Ravenclaws," one of the slightly-older boys complained; Harry thought maybe his name was Cormac.
They were almost to the stairs when the complaining boy was unfortunately proved right. An orange-furred head crested above the landing, his eyes so blue they were nearly glowing in the dim light. The troll that had somehow escaped the downstairs melee to go a-viking in the school couldn't miss over a dozen students, and roared a warcry.
"Run!" Percy shouted, clearly intending to hold the enemy off by himself while everyone else got to safety.
In hindsight, they should have run. If they'd all run, Percy could have fallen back. Cormac and his friends definitely did, their shoes loudly flapping against the stone as he followed through with what he'd already said was a better plan.
They should have run. But maybe it was two months of building Ron up into a hero in his own mind. Maybe it was simply family loyalty. Whatever it was, even under the very-real gaze of a heavily armed, seven-foot monster, Ron simply said, "Not leaving you, Perce."
That sold the twins. They had been about fifty-fifty on fleeing, but couldn't leave both their brothers to get killed. Their mother would be inconsolable. Lee Jordan looked panicked, but wasn't going to leave his best friends. Seamus was a tiny Irish madman and grinned his agreement to stay, brandishing his wand.
That left Harry, Hermione, Neville, and Dean. Hermione was still clearly about to do the logical thing, but in trying to visually convince Harry to flee, her eyes flicked to Ron as if to say, "I told you so." Later, Harry wasn't able to lie to himself and say he was always going to have stayed. He had to admit that he hadn't really been strongly attached to Percy, and might have let the boy make a violent, heroic sacrifice. Gryffindors were particularly in love with stories of going to Valhalla after a heroic last stand. But there was no way Harry was going to live with the guilt of also getting Ron killed. It really might have been Harry's fault.
Harry just gave Hermione a shrug, drew his wand, and yelled, "Gryffindor!"
Then all hell broke loose.
No matter what wizards liked to tell themselves about the power of magic, the situation was four teenagers that didn't need to shave yet plus six actual children with a couple months of martial arts training against a fully-trained, inhumanly strong, and supernaturally resilient adult warrior. Magic made it more even, but even a human warrior without powers might have still dealt serious injuries before being stopped.
Percy raised a strong shield, orange geometric lines spinning out perpendicular to the tip of his wand and bending back to trace a large circular plane in the air. The troll's mighty axe swing bounced off, but it was enough to shatter the magical construct into fading streaks of orange light and send Percy staggering backwards. Nine wands began to blast motes of the same light, but, to Hermione's earlier point about magical strength, the bolts from the lower-years seemed no worse than bee stings. Only Fred, George, and Lee's magical blasts seemed to do much of anything, and the troll quickly started to use his axe and armor to deflect those attacks.
With a fearsome growl, the raiding beast began to stalk toward the older boys to end their barrage, and the three, used to escaping from the teachers after committing pranks, split up in the wide corridor to make him pick only one as a target. He chose one of the twins, rushing forward and throwing the boy into the wall with his off-hand, knocking him senseless to the ground. Their attacker only spared the use of the axe because he was holding it out as an improvised shield against the other twin and Lee's scream of fury as they redoubled their efforts.
Percy finally recovered and shouted out, "Stunning Stupefaction of Skirnir!" He flung a bolt of the turquoise light of Vanaheim at the troll, which seemed to shudder under the impact but not fall. From his vantage shooting magical sparks, Harry could have sworn that the spell almost took effect, as the blue of the troll's eyes dimmed as it shook off the magic. With a roar of anger, the warrior turned and identified the prefect, again, as his primary threat, slowly moving forward through a fusillade of green-blue spells as the last standing pranksters tried everything in their arsenal to slow the creature.
The Weasley prefect wasn't idle, but the troll was now batting his spells out of the air in particular, willingly suffering the occasional prank spell to deflect more serious attacks from Percy. Running out of space as his back hit the wall, Percy looked in fear at the immense bestial man towering over him, smoking with half-landed spells and too close to escape or even cast against. The axe rose to end the troublesome opponent.
It was Ron who had the thought and gasped out, "Versatility!"
Harry picked up his roommate's idea, and managed to throw out an orange energy whip that wrapped the haft of the raised axe. There would be no way that he, alone, could hold it back, but fortunately the others got the idea and threw out tractor beams of their own. Hermione and Dean, who'd had more luck with the main levitation spell, yelled out, "Girding Wings of Lofn-Odr!" Even Ron finally managed an energy whip, his brother's imminent demise a suitable incentive.
About to bring down the executioner's blade, the troll glanced up in confusion as it barely budged, spotting six orange ropes and a knot of turquoise energy dragging it upwards and back toward the nuisances behind. Percy took the moment to duck and chant, "Total Petrification of Gleipnir!" The troll wasn't fully affected, struggling against the turquoise field of the body-bind spell, forcing Percy to continue maintaining his focus.
For several long moments the crowd stood in a fragile stalemate, each using all their power to bind the troll, unable to try something else for fear he'd escape. And then a viciously-thrown dagger punched into the joint of the troll's armor. The kids turned and saw the resident hag, Mistress Morgan, sprinting down the hallway, another knife already thrown and puncturing the troll's upraised arm.
Behind her, a pale face floated above flowing black robes, darker than the shadows behind them, as Professor Snape said something sibilant in Latin and manifested what initially seemed to be another orange shield with a faint flicker of purple at its edges, but with only two opposite quarters of the circle defined. He somehow swung this magical double-edged battleaxe through the air on a thin connection of orange personal magic, instantly decapitating the injured and restrained troll.
Only a few seconds after the other two professors, but coming from the opposite direction, a tabby cat bounded up the stairs and transformed into Rector McGonagall. "What is going on!?" she exclaimed, clearly not having expected the battle to have spilled upstairs. And then, in a question that made little sense to the students, she asked the other professors, "Did they reach it?"
Snape shook his head in negation as the conscious twin rushed to his brother's side. Trying to feel for a pulse, he sobbed out, "Don't be dead, George!"
To everyone's relief, the redhead on the floor cracked an eye at his brother's prodding, and managed to groan, "I thought… You were George."