A/N: Some nearly 190,000 words later and I realize that I blame Tom Hiddleston for all this. It might have become Hermione-centric in form (no matter how low I have fallen my first and only true love is writing with a strong female lead), but it was watching the first Thor that started all of this. For a story that began in December of 2013, it's become something of a monster.

To Ride Upon Svadilfari

-Chapter Fifty-One-

Hooke's Law

Sinmara, as a matter of Muspelheim courtesy, had offered him a meal before they departed to seek Vikar. And Harry had been flabbergasted to discover that only the Rjuendr, which was apparently some sort of warrior caste, ate flesh. All the other residents of Muspel had a diet of something he would never have taken for a food source and would have taken for granted on any other Realm. Nowhere had he glimpsed trees on Muspelheim in his flight, but it was wood that was the universal foodstuff of this odd race of giants.

Not something so dull as blocks of lumber, no, but elaborately carved creations that depicted all manner of things. Seeing his interest and ignoring his bemusement, Sinmara had explained that each of the creatures were by the patient work of a stone knife on wood, flavor and texture provided by differing species of tree, grain, and some complex system of cuts and location that sounded like butchering cattle. Sinmara had remarked that she preferred the burl and aromatic hardwoods, which was something she could eat on a regular basis only because she was high-caste. Lower-caste Muspelsmegir were left with the quick-growing softwoods such as pine relatives or, lower yet, bamboo relatives. The trees could live on this Realm only in special magical preserves, where powerful fire-giants manipulated the temperature to suit the trees. They were only places on the entire Realm where liquid water existed in any quantity.

Dragons could survive for longer without water than most creatures. They were a magizoological anomaly, reptilian and birthing eggs rather than live young, but they were warm-blooded by their nature. This meant that they could be active no matter the weather but in turn that they needed to hunt more often than their less active cousins. But again their nature came into play. Most of the energy generated by the food consumed by mammals went to regulating body temperature, but dragons had no need to that, so they ate comparatively little considering their size and were capable of taking most of the water they needed from their prey.

The problem? He would eventually need water on a scale that couldn't be met by eating the native wildlife. And being The Dragon interfered with most of his Wizarding magic, perhaps a result of being near-immune to most charms and spells. With great effort he could Apparate and several of the offensive spells were amplified by his native draconic magic, but more domestic spells simply didn't work. It hadn't been the inability to vocalize the incantation, because he'd been able to summon nonverbally for years, but the externally manipulated magic apparently clashed with the magic of his body. Which meant that his supply of magically preserved water and food was within easy reach of his human form but acquiring it meant risking being crisped to a cinder. His between form was heat-resistant, certainly, but he hadn't quite taken in the fact that there would be literal volcanoes. And, well, now that he'd seen the fire-giants he wasn't certain he wanted to reveal his humanoid form.

So there was a certain sense of urgency added to his task. That was what weighed on his mind as he watched Sinmara cup some sort of antelope-creature in hands and consume it with her flames, but he had been hungry before. Never hungry and a dragon, admittedly, but he had high hopes that he could at least find conflict quickly. His luck worked like that.

It didn't take the giantess long to finish her 'meal' and she rose in a sharp, startling movement that was akin to the resetting of her expressions on her face. He was beginning to get the impression that Sinmara was more flame than form.

"Come," she said and he rose as well from where he'd been stretched out along a wall. Not even a giantess's home was really prepared to accommodate a dragon of his scale.

"Where are we going?" he asked, just because he hadn't quite gotten over the novelty of effective communication in this form.

"You will see." Sinmara's long strides weren't really quick enough to match the dragon's most natural gait, but Harry bludgeoned a sulky and impatient Dragon into walking. The Dragon might have found it an indignity, but if it wasn't for the line of horns marching down his back, he would have invited her to ride.

Sinmara led him to one of the lava channels that he'd seen being used like canals earlier. He bit down on his tongue to prevent any comment about turtles, but it soon become obvious that wasn't Sinmara's intent. She waded in and if the blissful expression that her face shifted to was any indication, she enjoyed it to a point that it was awkward to watch, but watch he did as the flame about her waist brushed the boiling surfaced and flared into greater life. Her song shifted, not so much changing as becoming more.

Her body shifted and flowed, her hair spilling down to meet the reaching white flames that spun a fiery cocoon. And spilling from that cocoon was a graceful serpentine shape that dipped back into the lava, shaking the molten rock from its head when it reemerged in a sheer joy that he heard so distinctly that his heart ached with it. The firewyrn shrieked its happiness and The Dragon responded in kind, his wings fanning out without conscious thought and his neck arching as his own shriek mingled with hers.

The flames that licked along the crest of the firewyrm turned blue at the base and Sinmara's shriek turned into a crackle that he had to take as laughter. This ability is what separates me from the low-caste, Sinmara told him. They are bound in their forms. I am free. We can travel quickly enough to suit you, dragon.

With that, she plunged forward, lava roiling as she swam against the current. Harry took to the air, the blue line of flames along her back easy for his keen eyes to track. She led him away from the city, the land sprawling black and veined with molten rock as far as even his vision could reach. Time was odd, to a dragon, but he couldn't have been in the air for more than an hour before he saw the eruption of a distant volcano. In due time the cloud of volcanic ash reached him, making him sneeze and fly lower to the ground as visibility worsened, but Sinmara seemed undeterred. Perhaps most of their weather patterns were created by the volcanoes and this was no different than an afternoon rain in London. Sneezing harder this time, the sound accompanied by flame, he decided that he still preferred Midgard.

Eventually, by the time he'd been thoroughly covered in volcanic ash, he saw what seemed a line of fire on the horizon. As he grew closer, he realized that was only partially correct. It was fire, certainly, but not just a narrow band of it.

The Burning Fields, Sinmara told him before he was forced to fly away from the heat that boiled the very air close to the ground. The fire was so hot as to be invisible to his eyes, even if he could feel it on his scales, only the furthest edges burning with tongues of green and blue. Here we come to give birth and here we will eventually birth the end of all the Realms. The gates will open and the Fields will cover all with their bloom. At that time, we shall all eat flesh and be reborn as Mund-spilli, the world destroyers.

The Dragon could not frown, but that would have been the cast of his face if he'd been wearing a more human one. "But why? You're helping me now to put off Ragnarok, so why do you sound resigned to it?"

Because the prophecy says it will be so. So I can only defer what I can and accept what I cannot.

"That's just so incredibly stupid that I don't even have words for it," Harry rumbled. "Prophecy this, prophecy that. Do people on all worlds have nothing better to do than let words shape their futures? Belief is the only thing that makes prophecy function. If you don't like it, don't believe it."

He only believed Hermione's Arithmancy because it didn't just pluck an ending out of thin air. It produced the likeliest possibility out of an infinity of them, likely enough to not test the luck that had failed them on a semi-regular basis when the fate of their world was matched against their desire to return to it, but this was a different matter entirely. When you had nothing to lose, why not fight fate? Why this dire fatalism, this unquestioning acceptance? He'd seen evidence of it everywhere he looked and yet he still couldn't understand it. Even Loki, who still threw around that God of Mischief and Chaos title like it meant something when only a fraction of a fraction of Midgard's population even believed the gods of his pantheon were real, had talked about it like it was a foregone conclusion. Even Hel, who was entirely outside the cycle of life and death, had taken it for granted.

It was probably the single most infuriating thing about this version of the world, the heavy saturation of predestination. Harry had come to believe in later years they'd did a great favor to the Wizarding world by wrecking the Hall of Prophecies. He only wished it was so easy to make all these people forget the roles they thought they'd been born to play.

In the end, he'd never felt like he was any kind of Prophesied Savior. It's had its useful moments, other people thinking that, when they weren't accusing him of buying into his own press, but he'd fought a war first because Voldemort hadn't given him a choice and then because saving people was probably his most deeply engrained habit by that point.

But he'd always had a choice. In that cold, dreary tent, he could've chosen to live out his days in quiet obscurity with Hermione, damning the rest of the world to Voldemort and his rule.

He couldn't have done it. Wouldn't have done it, even if he'd been dropped into this version of the universe in that moment and didn't have to be confronted by the consequences of his actions. And that was why he'd made his choice. It had never been about a prophecy.

Sinmara made no response to his insult, which, after he'd had a moment to think about it, was probably a good thing. No need to get into an explosive row with his guide. But maybe he needed to convince Hermione that her next campaign should be targeted against prophecy in this universe, though he had a foreboding feeling that it was going to be Asgard who bore the brunt of her new Beings rights campaign. Merlin's pants but that could get ugly. It really would be best for everyone if they went back to Midgard and Hermione used that mind of hers to argue Tony Stark out of any and all mischief he'd been up to. Though what they'd do when Tony'd lived out his life was still rather up in the air. It would be difficult to remember that they were with people who lived on different scales than they, but in fifty or sixty years it was going to be really obvious.

If Jane stayed with Thor, that was all well and good. Extending the life of one person was one thing, to try and extend the lives of every person they grew close to on Midgard? That was where love mixed with the Dark Arts, which twisted it until it was unrecognizable.

It was these sobering thoughts that carried him over the Burning Fields and kept him beating his wings until Sinmara slowed her pace. Harry swooped lower and her voice carried up to him. Ahead are the lakes. There we shall find the one you seek. Land and walk the rest of the way, dragon.

"My name is Harry," he offered as he did as she asked. He'd introduced himself before, of course, but Sinmara had continued to refer to him as 'dragon'.

Silence was his answer, but he didn't let it perturb him. Because he could hear another song building, low and dissonant and haunting. And so strong that it seemed fit to rattle his bones. The Dragon keened silently, fire boiling his blood and emboldening his heart, scales coming alight with heat along the underside of his neck and his wings bronzing more darkly.

Something heard him, for the surface of the greatest of the lakes roiled, then the surface was breached by something Surtr could have ridden to war. He was immense, solid and heavy through the body like a Komodo dragon, titanic blunted talons crushing the ground as he heaved himself onto land. A putrid stink filled The Dragon's nostrils as the creature trumpeted a challenge, spreading its own wings in a display of challenge. They were stunted and unfinished, like the creature had been birthed too soon, one crumpled awkwardly against its side and the other developed only to the first joint.

"I hunger," it said in a parody of speech, the words hissed and slurred. Opening its maw exposed row after row of teeth, marching like soldiers into the back of its throat. "I hunger. And when I am full, I shall break that false-god's body upon my teeth like a ship dashed upon the cliffs. Is that why this worm has come, to be devoured?"

"I thought Vikar was a person. A dead one, but still, y'know-," Harry managed through gritted teeth as he wrestled down The Dragon's instincts, which were going to get them killed in this Realm yet.

He came as the shadow of a man, but his hate was strong enough to lead him to do something very foolish. He devoured the heart of a fire-giant and was reborn in flame. He has been devouring the lesser-caste and the unwary ever since. When his wings are fully formed, he will take flight. You would be wise to finish your task before that happens, dragon.

"I'm open to advice. And help." It took a superhuman effort not to ask why they hadn't killed Vikar when he first started eating fire-giants instead of letting him grow into this monstrosity, but common sense seemed to be in short supply in this version of the universe. Not that they'd had a lot to spare in his either, but this was beginning to get ridiculous. "I'm going to guess I can't just breathe some fire at him and call it a day?"

He was forced into quick flight as the abomination belched a concentrated stream of what appeared to be lava at them, the super-heated plasma hissing as it impacted slightly cooler rock. Harry hovered at a distance that would make it easy to avoid the stuff, even if he didn't quite think himself out of range. He circled his opponent, noting that Sinmara had disappeared, but he put that out of his mind as he tried to see what advantage he might gain from the terrain.

He'd had the advantage over every enemy he'd encountered since he became The Dragon. There was no armor that his claws couldn't breach, nothing that his fire could not incinerate, his song greater, fiercer, brighter than any other he'd encountered. Not even the Tesseract had caused him fear, though the Aether had tempted him to greatly that even the memory of it in the midst of battle made him ache to gift it to his hoard. But this was different. This was a challenge to The Dragon as Surtr had been a challenge. The difference was that Surtr's song, when he'd heard it in its truest form, wasn't so disjointed and sinister.

Vikar's constructed body looked slow and unwieldy when compared to his own sleek lines, but he was about five times his length and many times his weight. Flight was good, but lava was still running through the channels created by his scales and Harry had no idea what the melting point of a magically-augmented Hungarian Horntail was. He wasn't that eager to find out, either.

But he would have to do something eventually and given that little opening speech, he somehow doubted all could be made sunshine and rainbows with words. At least he couldn't. Maybe they should have given Loki and Hermione this one. On further consideration, it should have went to Loki, who seemed to have some issue with his ability to freeze things to the point of no molecular activity, but who could have made an exception.

Then again, the whole point was that this was supposed to be nigh impossible, so considered from that angle, this was perfect. It was also the best argument ever presented as to why even so much as leading Hel on would be A Very Bad Idea. Hel had ruled her Realm as an absolute ruler in every sense of the term for far too long for the kind of marital disagreements that happen in any relationship to be a pretty picture. Seeing the creature below had also served to remind him that his truest form was a dragon and this was a world in which coupling with a dragon while you were a different species was no guarantee that he wouldn't father Nidhogg or something.

He had no idea what that said to his character or lifestyle, that most of his important life decisions were made before or during life-threatening battles, but there it was.

So, having that settled put part of him at ease, but no closer to any idea of what to do about Vikar. The Dragon wanted to make some input on this, but The Dragon had already made a blunder on the scale of Arthurian legend with Surtr, so he really wasn't in the mood for the 'rend, tear, emerge victorious' plan that The Dragon thought was suitable for dealing with any enemy large enough to see.

Harry ran with the assumption that destroying Vikar's body would be enough to send his soul to Helheim, because the kind of magic made to harm or manipulate ghosts was so Dark that even those Wizards who wouldn't flinch at an Unforgiveable avoided them. Horcruxes were a good example of that and that involved only one's own soul. Hermione might have known the spells-Harry would never put anything outside Hermione's just in case mentality on the Dark Arts-but Harry had had Voldemort in his head and that was quite enough.

Something that resembled a plan only in the vaguest sense of the term spawned itself in his brain as he wove his way through the arcs of lava that Vikar was using his tail to cast his way. He knew it was the plan the moment his mental Hermione-voice shrilled, "Absolutely not, Harry James Potter!" There was one advantage when he did the planning and not Hermione. Contingency plans were for those who lacked commitment; if his went wrong, they had the distinct advantage of not having to explain why to Hermione. Though that wasn't quite right-it made him sound a little too much like Thor. It was better to say that his one plan was just generally very flexible. He knew the main point and made up the rest as he went along.

The main point to this plan was a weapon he'd never had the advantage of in the Wizarding world.

Caladbolg.

But he couldn't wield Caladbolg as The Dragon; his magic would hold against the ambient heat in his between-form (or at least he was determined to think so, despite his earlier thoughts to the contrary), but he wasn't certain his shields wouldn't falter on direct contact. Whatever these lakes were, they had a magic of their own he could now make out underneath the chaotic riot of Vikar's song. It was a thing of unmaking, of primal destruction, but also a thing of creation, diametric opposites not at war but in a harmonic ebb and flow.

So he was giving himself one strike. With Caladbolg, it would be enough. It would have to be enough. A piercing blow, though Caladbolg's specialty was sweeping slashes, if he could manage to find something resembling a vital organ. Vikar was a dragon built of hate and molten rock; he'd hate to split the thing in twain and have it turn into two of the damnable beasts. (Hermione had thought the thing with the hydra was funny. Harry not so much.)

Confident that he at least would win when the match was based on speed, he shifted the angle of his wings, hardly needing to beat them at all with so much heat radiating upward.

It was almost a fatal mistake, the ploy with the lake-lava nothing more than a child kicking up water to entice an opponent closer. Vikar moved with the same disorienting speed as Sinmara, rebuilding his body in another place rather than shifting it. But Sinmara rose out of the lake as a chain of fire, her burning body closing around Vikar's jaws with the finality of Fenrir bound. That is to say, Harry knew the reprieve wouldn't last.

So he sharpened his ears as he banked sharply, listening intently for any fragment of anything that sounded like a human being. At first, in what could only be building panic, he thought he could hear nothing, but then, on a final circle that took him so close he could smell the heat that radiated from Vikar, he heard it.

It was small and transient, fleeting and faint, everything that was at odds with the storm of his magic. It was humanity, powerless and brief when compared to the greater forces that lived in the wider universe. It dwelt in his right eye.

Gallows humor prompted the obligatory 'windows to the soul comparison', but when his opportunity came, he grabbed it by the throat. Vikar writhed in his bonds, Sinmara shrieking with mingled rage and pain. For but a moment, his head was angled in such a way as to turn his eye upward to where Harry awaited. It was like looking into a burning sun, but Harry shed his scales and summoned Caladbog to hand. He needed no wings, putting his full weight and the momentum of his fall behind the sword that could cut through mountains and destroy armies entire.

It was his turn to scream, this time with pain, as he sunk knee-deep in a fluid that seeped in his armor and burning his flesh. But his pressed onward, with human determination and draconic strength, and the rainbow of light from Caladbolg was a column that sheared the remaining volcanic cloud and punctured the obsidian earth deep, deep beneath the lake.

Vikar's cry of despair echoed, but there was nothing he could do as his body began to crumble away, leaving only a wasted wraith of a man. Sinmara, as the giantess, caught Harry before he could really test his shields against lava and he was very glad of it, because he had a sneaking suspicion that the muscles in his legs were better done than one of Mrs. Weasley's corned beef sandwiches.

"Why?" Vikar spat at him accusingly. "Why did you stop me? Odin tricked me to my death! What king of the gods? He is nothing more than illusions and bloodlust."

Harry blinked at him slowly. "Are we talking about the same guy?" He was surprised to find that even now Vikar still spoke in the language of fire, or whatever common tongue it was that allowed them all to communicate.

"It is no surprise you do not know the story. After all, who tells tales of their sacrifices? I was a king and like all kings, there came a time when I went to war. At my side was a man whom I thought a friend, favored of Odin. My ships were becalmed and our supplies low, so he suggested that we make a sacrifice to Odin. A symbolic sacrifice, with a king as its centerpiece. But the reed he wielded revealed itself a spear and the noose around my neck a snare that couldn't be escaped. The Gallows God took what he pleased that day! A god of lies! A mockery of divinity. Why would you not let me rip away the illusion that conceals what he truly is? Why?!"

He lunged clumsily at Harry, but already his power was fading, a strong, chill wind blowing him onward to Helheim. Harry's thoughts followed him there, to the seat of Hel. "Sending me to a man with a story like that...what are you planning, Hel?" Then the pain became too much and darkness swallowed him up.

A/N: David Attenborough was narrating 'Life in Cold Blood' in my television while this chapter was being written, so every time The Dragon did anything there was a voice in my head going, "And here the male of the species shows his dominance by..."