The mood at the lake was tense. Bleachers had been hastily arranged around the shore, filling with guests and students to watch the task. Well, what they were mostly watching was the headmasters getting shouted at by Fleur's father.
"You will send your teachers down there and they will retrieve my daughter!" Maréchal was yelling, loud enough to be audible even to the Gryffindors walking up. Harry hadn't even known that he was back at the school. But wait, his daughter?
He managed to find Fleur quickly enough, suited up and looking distraught under a hastily-erected pavilion tent. They hadn't even gotten them breakfast this time, the event had been thrown together in such a rush. "My little sister! Zey took Gabby!" She said as soon as Harry was within earshot. Only a glance across the beach at her clearly-incensed father checked her step toward Harry for comfort.
He nodded grimly, his friends having left him to stand with the other challengers as they found seats. "Our friends, too. Hermione, Luna, and Cho. One hostage for each of us."
"Hermione did not make it back?!" Viktor said, walking up in his own swimwear. Cedric was right behind, face drawn as if he'd already heard.
"The Norns," Harry repeated. "They must have arranged things so they'd all be walking near enough to the lake to get snatched."
They all looked as the white viewscreen levitating over the lake suddenly lit up with an underwater scene. Oona had been working on getting the dark elf cameras to project across a convergence, assuming that nobody would be able to see anything if the screen was underwater. It looked like she'd figured it out. Which also meant that the portal to Jotunheim must be right below where the screen was hovering. On the overcast winter day, it would probably even be easy to see from the stands.
Fleur's father stomped away from Dumbledore toward them and said, "The headmaster assures me that the Norns would interfere with any attempts for adults to intervene." A whole series of emotions flitted across his face, and Fleur took a step back as if slapped—Harry assumed that somewhere in there was anger that Fleur's entry into the competition against his wishes had put her sister in danger as well. "Bring Brindille back," he ordered her, gave a curt nod to the other three, and stomped off.
"Brindille?" Harry asked.
Fleur wiped away a tear before explaining, with a bit of distaste, "French for 'twig'. Not even budded yet. I call her 'Gabby' since she is so talkative."
"We'll get her back. We're going to get them all back," Harry assured her. Nods of assent came from the other two boys.
"What about air?" Cedric realized. "How are we going to bring them back from underwater?"
"How much of that gillyweed potion did you brew?" Harry asked.
Cedric nodded in realization. "Hopefully enough. Good idea." He patted a belt he was wearing, as if to show where the other bottles of potion were. It was a little odd that he didn't immediately pass it out to all of them, but maybe he had it in only a couple of vials that they'd need to portion out.
"Challengers!" Dumbledore's voice boomed out from the judge's podium in front of the stands. Harry looked over and saw that, indeed, Percy had wound up subbing in for Crouch, who presumably had been too far away to make it. The Ancient One was missing as well, probably not able to travel all the way from Earth on such short notice. "Time is wasting and we need you to begin. I trust you all understand what is at stake?" Grim nods from the quartet were his answer, so he proceeded, "Then, begin."
They rushed down to the shore of the lake, each preparing their methods of underwater survival. Harry pulled on his diving mask. Fleur began to coalesce her glamour around her head to fool the universe into thinking she had air to breathe. Viktor did something similar, conjuring a sphere of orange personal energy around his head and turning on the oxygen tanks Harry had loaned him—Hermione had worked with him to basically create a shield against water as a diving bell, rather than making a deal to transform himself. Finally, as they reached the water, Cedric took a swig of greenish potion, gills immediately forming along his bare neck and sending him gasping to breathe water instead of air.
Following the refracted light of the video projection, the convergence wasn't far beneath the surface. Which meant that it must not be far beneath Jotunheim's surface, either, lest the pressure differential have just created a waterspout that they couldn't hope to cross.
Sure enough, as soon as they swam through the portal the water dropped in temperature to as near-freezing as it could get without becoming ice, but the pressure stayed consistent. Clearing the iris of the convergence, Harry glanced up and saw it was basically flat against an ice sheet that couldn't possibly be that thick, but was certainly dense enough that they shouldn't expect to try to blast through it as an escape. An unbroken expanse of softly-glowing white as it diffused the sunlight above, Harry momentarily became disoriented about which way was up.
"The enemy gate is down," he told himself, focusing on finding where the fomor must have taken his friends.
While the adults didn't seem to think they could mount the rescue in place of the challengers, they'd at least done what they could. Someone had cast spells to make brightly-glowing orange balls of energy form a line into the darkening water ahead and down. And the cameras were already spaced out ahead, moving through the water almost as easily as they had the air on Muspelheim.
Harry checked the three around him, pointed, and they all got to swimming.
The trek was cold, oppressive, and silent. They were in deep enough water to not even see sea floor, and if there were any kind of fish on Jotunheim, they were at least staying away from the lights. Which meant just a long, undifferentiated swim with nothing much to look at except the markers of conjured light ahead in the blackness.
As they passed each light, Harry glanced at the others. Cedric seemed oddly unbothered, looking around bemusedly, as if he never thought he'd wind up in such a place. Viktor's face was tense within his bubble of air, spoiling for something to fight. Fleur's lips were pinched in concentration, and Harry worried for her; she'd never really been completely confident in her spell. For his part, the enchanted face mask seemed to be working well, though the cold was beginning to sap through even the warming runes he'd put in his suit.
Nothing attacked them on their long swim through the void. Harry could only assume that the fomor hadn't bothered to leave guards in their path, after centuries of never having to worry about attack from outside of their frozen redoubt below the ice. Finally, their eyes began to resolve a deeper blackness ahead, but it was unclear whether it was an underwater mountain or a fully-constructed megastructure in the deeps. The trail of magical lamps led them to a large hole in the side of the structure, too perfectly circular to be anything but manufactured.
Once they were inside, that's when the guards noticed.
The interior of the structure was lit, if faintly, which was almost like a spotlight as their eyes had adjusted to the sunless depths. More surprisingly, it didn't appear to be completely underwater, as there was a definite shimmer of water surface above them that their assailants dived into. One second, it was the four challengers swimming into the submerged room, the next there were two large forms splashing in.
Keyed up and spoiling for a fight, the battle was confusing but quick. Harry lashed out with an energy whip. Viktor launched a cutting spell of orange light edged with purple. Cedric managed some kind of lance of power that was almost invisible in the water.
Fleur attempted to help, but then desperately began swimming for the surface above them.
The fomor tried to fight back, but they somehow hadn't prepared for the energy brought against them. And while they were natural swimmers, the ice conjurations that jotun-kind could manage were actually more effective in the air. Viktor took a grazing blow from a conjured ice spear, and that was the worst their team suffered. Harry tried not to think too hard about it as the bodies of the fomor stilled, bluish blood leaking into the previously-clear arctic water.
They pulled themselves to the platform Fleur had already climbed atop, where she was hacking up a lungful of seawater. "You okay?" Harry asked, removing his mask and ready to make use of his first aid training if she couldn't clear her airways on her own.
"I cannot manage ze breazing spell and do anyzing else," she admitted, coughing out the last of the near-drowning. "I 'ope ze rest of zis place 'as air."
"I don't know," Harry said, finally getting a good look at the room. It was basically straight out of the water base level for any "near future" first-person shooter. Indeterminately-sci-fi materials were showing their wear from centuries of maintenance. All of the construction was just alien enough that it clearly wasn't made in any era or culture of Earth. The illumination came from light strips embedded in the architecture, which in this room was basically just an oblong moon pool surrounded by a two-yard-wide lip of some kind of probably-plastic running into walls of a similar material up to a ceiling too short for a full-height jotun to be comfortable.
As they looked at the bodies of the fomor bobbing to the surface of the pool, it was apparent that they were not full-height jotun. They weren't even as tall as Hagrid. Pasty-skinned and twisted, they reminded Harry of nothing so much as an upscaled Gollum from Lord of the Rings, albeit with slightly froggier facial features. Jotun lived long enough that there shouldn't have been enough generations in the last thousand years to inbreed that heavily, but maybe they'd had a dwindling gene pool for long before Odin defeated Jotunheim and this place was cut off?
The important thing for Fleur's concern was that the door out of the room seemed pretty low to the floor. Harry got the sense that the amphibious guardians wouldn't think much about setting the place up as a bunch of pockets of air linked by water. He was honestly curious what kind of alien tech was making the air pressure involved manageable. "Might dip back down into the water at points," he shrugged.
"Well, I'll go as far as I can. I 'ave to rescue my sister!" That statement was fully framed in one of the cameras that had risen to follow them into the room.
"Go ahead without me," Cedric told them, still bobbing with only his face out of the water. "I'll be right behind you when my potion wears off. I'd been hoping the whole thing was underwater."
"You think there's svitch?" Viktor asked, striding over to the doorway and trying to figure out how to make it work. It was clearly some kind of high-tech pressure door, but lacked the iconic center-mounted ring handle, for all that the door itself was also circular and slightly convex for a better seal against the pressure differentials involved.
Harry turned his Stark-trained eye on the situation and thought aloud, "It's held up for centuries in these conditions. Won't have a lot of moving parts. They wouldn't really need keys if they're the only ones down here, but maybe they have some kind of implants that tell the door to open?" He definitely didn't see any switches or buttons, as Viktor had noticed, so they had to be automatic in some way. Then, with a shrug he said, "Let's hope magic works."
He'd spotted a line running vertically down the door and folded out the knife Sirius had given him, which was supposed to have unlocking enchantments in it. Feeling along the seam with the knife and extending his own personal energy long practiced at picking locks, he felt something catch inside and pushed. With a hiss and a heavy clunk, the door folded up and into the sides of the doorway, revealing the path beyond.
Even a lavish base created by one of the wealthiest aliens in the universe wasn't going to waste a ton of space on hallways if it didn't have to. The door opened directly to a larger chamber, also round, perhaps a dozen yards in diameter. Ramps along the walls led both up to a gridded metal catwalk and down into water, presumably to other underwater areas. The floor was covered in puddles of water, like they were having trouble keeping the pressure regulated to keep the sea level from rising, so the room regularly flooded.
The light in the room was from the both the same strips and the twinkling of tons of multicolored indicator LEDs (or the alien equivalent). As their eyes resolved the distance, it was clear that an insane array of small, glass-fronted boxes were mounted to all of the walls, the colored lights some kind of indicators about the status of the contents. None of them seemed to be big enough contain their missing friends, but there was no telling what kind of smaller treasures were within.
Also, there were a half-dozen fomor, so it wasn't like they had the time to browse.
They hadn't noticed in the water, but the inbred jotuns didn't really wear clothes other than some briefs for modesty. So the oncoming wall of pale, clammy skin was almost as intimidating as the battle roar of the giants attacking the first invaders they'd had in over a thousand years.
"Fleur, cover fire?" Harry half-suggested, half-ordered as he moved to stop the two rushing down from the upstairs. He conjured a shield in his left hand and a "blade" of orange energy in his right: after a lot of practice, he'd managed a construct that worked more like a saber than a club.
"Got it!" she agreed, whipping out streamers of glamour that disoriented and slowed the oncoming fomor. Meanwhile, Viktor had decided to tank the other four, loosing blasts of purple-tinged magic and then forming a larger shield to block their charge from the middle of the room.
Harry lost situational awareness after that, dueling on a slippery metal stairway with two larger foes. He blocked ice daggers with his shield. He slashed with his sword. He tried to use the closer one to block the further, the stair not really wide enough for both. He appreciated that Fleur's magical attacks kept them from being able to land effective hits.
Realistically, three teens should have been crushed by twice as many giants. But the fomor had seemingly not put in the effort with their combat skills after a millennium guarding a vault that nobody wanted to rob. They were already clumsy before Fleur used her magic on them, relying on brute force. Meanwhile, Harry had been training obsessively for years. His footing started to get even more precarious as jotun blood coated the stairs from the slashes he was dealing.
The fomor higher up the stairs started to consider retreating as Harry staggered his companion, the closer enemy clearly about to keel over from pain and blood loss. But then it gave a froggy look of triumph at something it saw behind him just as Fleur shouted, "'arry!"
Harry spun around, realizing that a seventh fomor had slipped in behind him, probably from one of the ramps leading down into the water, and was already swiping down at him with an ice dagger the size of his arm. From that angle, there wouldn't be much he could do but hope to deflect it and open himself to the fomor above him on the stairs.
Then the attacker grunted in surprise and keeled over, missing Harry and tumbling off the stair railing onto the floor below. Revealed behind it, Cedric gave him a nod and said, "Alright, Harry?" His arm and a surprisingly-large dagger were coated in blue blood from where he'd stabbed the giant in the back.
"Thanks, Cedric," Harry agreed, managing to duck a pained swing from the closest remaining fomor and thrusting to hamstring him. The one above was already stumbling up the stairs to flee, seeing the odds so thoroughly evened. "Guess the potion wore off?"
"Just in time, it looks like," Cedric agreed, moving beside Harry to menace the guards.
Within a few more moments, there were three dead Fomor at various places around the room and four fleeing back into the station. "Everybody okay?" Harry checked, realizing he was bleeding a little from a couple of cuts on his upper right arm that he hadn't fully deflected.
"I'll heal," Viktor shrugged, more cut up than he had been before entering the room, and applying pressure to a couple of the wounds.
Fleur and Cedric hadn't taken any hits, though Cedric was a mess until he dipped down into the water tunnel to clean off the fomor blood. That drew Harry's eye to the signs in alien language, his implant kicking back on and superimposing the meaning. "It figures," he told everyone as he pointed, "that one says 'Living Subjects.' Bet they put them through a water tunnel to make it harder to escape."
"I'm not sure if I can…" Fleur said, clearly still shaken by her near-drowning.
"My potion's not great if it's just a little while under the water," Cedric admitted.
"Ve vill retrieve them," Viktor nodded.
"Yeah, just guard the room so they don't get behind us," Harry agreed. He glanced at the distance from the dip down underwater to the lip of the moon pool and figured it would be a lot easier to charge across it holding your breath (holding your gills?) than potentially swimming through the tunnel. "Cedric? The potions for the girls?"
"Right," the Hufflepuff boy nodded, putting the second knife he'd drawn under an armpit to hand over a couple of vials of the green potion. Harry hadn't been aware the boy was a knife fighter, but he seemed prepared to fend off an army of fomor. Fleur had, herself, produced a smaller, silvery blade in case they got up on her without Harry and Viktor to block. "Good luck."
"You too," Harry told him, lowering his mask and following Viktor into the underwater tunnel.
Like everything else, the tunnel was lit by small strips of lighting at the corners, and bent around through multiple twists. Harry wasn't sure if it was a deliberate attempt to be disorienting for escapees, or just a consequence of it wrapping around other rooms. Conservation of space seemingly went out of the window when the tunnel was defensive: it was easily a hundred yards long. It took just long enough to traverse that a normal person would struggle to hold their breath all the way through, particularly if they weren't confident about the route and were moving slowly. A few false tunnels even junctioned in at points, taking time for Harry and Viktor to make sure fomor weren't lying in wait. They would further confound someone holding their breath to try to make a swimming escape to the main chamber.
The room they eventually surfaced in was similarly laid out to the one they'd left, a big spherical habitat with the walls covered in displays. These were larger—some were much larger—fit for housing people and creatures.
And for most, the status lights were off and there was nothing inside but mummified dead bodies of captives that had long-died after lives as bugs in a jar. It was dire.
A single fomor was still in the room, turning as they emerged from where he'd been keeping an eye on the wall of containers. Harry spotted movement, and hoped it was his friends, but had to focus on the charging guardian. "You sure you want to do this?" he asked, hoping he was getting translated. "We've already beaten your friends."
The giant shouted something to him that didn't make a lot of sense. "Kvok prot hart clan vazer clektion!" He was sure his implant should have Jotun, so maybe whatever dialect they were using had drifted?
By the time Harry and Viktor had defeated the giant—only maybe twenty seconds, with the ability to flank and having learned how they fought—Hermione and Luna were already out of their compartments and moving to free Cho and Gabby. "We would have been out earlier but they kept watching us," Hermione informed the boys.
"Happy to be a distraction," Harry shrugged for the cameras.
"I suppose we should have learned one of your water traversal spells," Luna observed, leading the small elf that must be Fleur's sister over to the edge of the room. She looked maybe eight years old, her elven beauty manifesting as doll-like features under her own golden hair.
"We have potions. It's going to be a sprint to the exit only able to breathe water, though," he told them, producing Cedric's gillyweed draught. "How'd they even get you in here?"
"A rather clever hollow ice conjuration," Luna explained.
Viktor hugged Hermione once she walked over with Cho, who asked, "Where's Cedric?"
"Where's my sister?" Gabby asked, maybe in French and his implant was translating it.
"Outer chamber," Harry explained, passing Hermione and Cho the other vial of potion. "We're going to have to swim for a couple of minutes, then you'll need to run across the room to get back in the water. Because you'll only be able to breathe water. Make sense? Let's go!"
The girls all shared a swig of the potion, and Harry hoped it would be enough to get everyone to the surface. He seriously considered smashing a container and taking a skeleton as a souvenir, but that seemed almost as ghoulish as leaving them on display. Plus, he wasn't really sure which ones were important, historically.
No fomor had managed to get around behind them in the tunnel, and in a couple of minutes Harry and Viktor preceded the girls into the main room just in case, finding Cedric and Fleur in a running battle with a slowly-increasing number of fomor that had gathered reinforcements and come back to the room. It was fortunate that they'd only been gone for five minutes. "That way! Go! Go! Go!" Harry gestured at the girls currently only able to breathe water as he joined in to cover the escape.
Fleur was clearly relieved as she spotted her baby sister in the crowd of thoroughly-soaked young women dashing toward the moon pool. "Fighting retreat?" Cedric suggested. "Or do you have a cunning ploy?"
"I'm not really the cunning ploy guy," Harry answered, firing off some bolts of magic. "Let's just get out of here."
Fleur ducked on the way out of the door to retrieve a small pile of stuff she and Cedric had apparently smash-and-grabbed before the Fomor came back in, and they all retreated through the doorway. "How ve close it?" Viktor asked.
Harry hadn't actually thought of that, but said, "Where there's a whip, there's a way?" He cast his energy whip into the mechanism and yanked down, which seemed to be enough to reassert the door's desire to close off the rooms. As it thunked closed between them and the fomor, he asked, "Think you can… spot weld it?"
"Maybe?" Viktor agreed, weaving his arms to summon a jet of his own personal energy to try to burn the seam closed, the purple of the dark magic succeeding in amplifying his intention to melt. "Good enough?"
"It'll have to be, let's go!" Harry said, not actually thinking it was a good weld but hoping it would hold long enough for them to get ahead.
Fleur and Cedric had already dropped into the moon pool ahead of them, Fleur hopefully able to maintain her breathing glamour all the way to the surface. Harry pulled his mask back down and jumped in, with Viktor right beside him and the remaining cameras diving behind.
The swim to escape was less sedate than the one in. They had four more people to manage, who had not dressed for the swim. Fortunately, the gillyweed potion was supposed to provide some level of adaptation to cold water on top of the gills, or the girls might have suffered hypothermia on the way out. They probably were all going to suffer the bends, as fast as they were swimming to stay ahead of any pursuers, but they'd confirmed weeks previous that it was something that Madam Pomfrey could fix.
There was nothing to do but swim like crazy, and hope there weren't fomor on their heels ready for payback and much better at maneuvering in the water.
They weren't going to make it. Seeing the glittering light of the projector above them, Harry glanced down and made out nearly a dozen pale forms gaining on them from below, illuminated by the magical lights that had led them to the base. Gabby, in particular, wasn't a strong swimmer, and was slowing down Fleur and Luna trying to help her. There was nothing for it. Harry turned and managed to manifest his shield and energy sword, at least hoping to delay the pursuers enough to let everyone else get to the surface.
So he was surprised to see a shimmer in the water and then all of the giants simply disappear a half-dozen yards away from him.
As he turned in confusion to continue his swim up, he spotted saffron-robes off to the side, the Ancient One sitting lotus-position in a pale bubble of air. In the time they'd been below, she must have managed to get there after all. She winked at him, floating along after. He realized that she must have shunted the fomor into the Mirror Dimension, nodding and continuing his way to the surface.
He really needed a sling ring.