It's Thanksgiving Day in the US, and to say thank you to all of my readers - especially those who offered messages of support since my mom's passing - here's another chapter.

HP HP HP HP HP

7 December 2014

Tony resisted the urge to call out Honey, I'm home, as he strode into the workshop in the original Stark Tower in Manhattan.

He hadn't been back since he'd taken off for London more than a month ago. With only three weeks until the first task, it had seemed silly to travel back and forth, despite the relative ease of portkeys. Besides, he added to himself alone, he would've been far too distracted by the danger to Harry to concentrate.

Now, though, Tony had scouted the Black Lake, Harry and Neville were safely ensconced at Avengers Compound - an easy commute for Iron Man - under the tutelage of two men who were fully capable at both magical and non-magical combat, and Sirius had, after admitting that he couldn't match either DiNozzo or Gibbs in the combat mentality, returned to Manhattan with Tony to resume tutoring Hermione in Defense against the Dark Arts.

Which meant Tony was free, finally, to do what he did best: let his mind wander and create things.

"Where was I, J?" Tony asked as he poured a cup of coffee from the machine JARVIS had started the moment Tony headed for the elevator.

"Most recently, upstate," JARVIS replied, and Tony almost dropped his coffee.

"I see the smartass subroutine is in fine form today," he said.

"As you prefer, Sir. To answer the question as you meant it-" and JARVIS began to describe four of the projects Tony had in progress.

Of the four, a refinement to breeder reactors to reuse spent nuclear fuel sounded the most interesting at the moment - if only because making it work would give him an opportunity to needle various senators and other Congresscritters that the rest of the world would be benefitting from the latest Stark Tech long before the United States, thanks to a nuclear energy policy that was uneven at best.

In some ways, his arc reactor technology made nuclear technology obsolete - or so the SI Board of Directors had tried to argue - but, as he'd argued right back, it never hurt to have backup plans, even a redundant backup plan.

He took another sip of coffee, set the cup aside, called up the plans in holographic form, and settled in to work.

Some time later, when he was up to his eyebrows in blueprints and up to his elbows in a scale model, JARVIS' voice pulled him back to the present.

"Sir, Mr. Odinson is calling."

"Who?" Tony asked reflexively, then realization hit. "Oh. Thor. Right. Put him through."

In the half-second before the screen came to life, Tony realized his coffee mug was empty. He stood and was rolling his shoulders when Thor spoke.

"Greetings, friend Stark."

"Season's greetings to you," Tony replied, grabbing his cup and starting for the machine. "What's up?"

"My mother has finished her examination of the elf, Kreacher."

"Oh?" Tony looked back at the screen, briefly, before returning his attention to the cup so he didn't overfill it and burn himself. "What'd she find?"

Then what Thor said registered. "Wait - your mother? Isn't she the queen of the gods or something? Why would she be examining an elf?"

Thor's expression conveyed his amusement at the question. "She's a practitioner of seidr - what you might call magic - one of the most skilled at the art in all of Asgard."

Huh. Tony made a mental note to get familiar with Norse mythology. "Carry on."

"I had thought that perhaps Kreacher and others like him were descendants of one of the two types of Midgardian elves," Thor said. "But Mother has determined that is not the case."

"So what is the case?"

"The elves are beings, not creatures."

Tony paused with the cup halfway to his mouth. "You say that like there's a difference." On the screen, Thor nodded. "Explain."

"You and I are creatures," Thor said. "As are dogs, cats, horses - any living things that evolved on our planets of origin."

"Fair enough," Tony said. "Though some people would object on principle to being called creatures."

Thor shrugged. "The Asgardian terms would mean nothing to you, so I have chosen terms to help you understand."

Tony couldn't argue with that, and he waved his cup in invitation to continue before taking a sip of coffee.

"The elves are beings - apparently living things who were brought into existence by creatures, rather than evolving independently and naturally." Thor hesitated, looking momentarily uncomfortable, before adding gently, "Not entirely unlike JARVIS and JOCASTA."

It was like Thor had hit him in the gut with Mjolnir when he wasn't wearing the armor. "What-"

"'Tis not evil," Thor said, and Tony held up a hand as he tried to regain some equilibrium.

Oh, the explanation made sense - and so did the analogy, however much it had initially shocked him. The implications, though, were staggering, and Tony would be considering them for a long time.

"No, I get it," Tony said when he had ordered his thoughts. "How do you know this?"

"Seidr practitioners can discern the course of fate, tracing forward and backward," Thor said. "As I said, Mother is one of the most skilled, and she could trace Kreacher's fate back through the generations, the centuries, to his ultimate origin and, through him, all the elves."

Tony made his way back to a stool. Being seated for whatever came next was probably a good idea - as was setting aside a cup full of very hot coffee.

"And that origin was the creation of elves?" he asked.

"Aye. Wizards created them millennia ago."

"For what purpose?"

Thor shrugged again. "Who can say? Fate can show only events, not motivations."

"Right, okay." Tony picked up his cup with care, took a sip, and replaced the cup before speaking again. "So a bunch of wizards - I'm assuming it had to be a bunch? Not one or two guys hanging around on a Friday night and one said to the other, hold my beer, I'm gonna try something."

Thor's lips twitched. "Indeed. It was a massive undertaking, that much is certain."

"A bunch of wizards got together and created elves - house elves, to distinguish them from other races of elves you mentioned. Why would they create someone as excitable as Dobby, as irascible as Kreacher?"

"They did not," Thor said. "As far as Mother can determine, house elves-" he made a moue of distaste "-were created as helpers. But, whether through accident or design, though most likely accident, the magic that created them is wearing off."

Tony frowned. That sounded bad. "Wearing off?"

"Because the magic that created them has not been renewed, each successive generation receives less of an…infusion is not the correct word, but I believe it is the closest in English. Each generation receives less of an infusion of that magic, which leads to an instability in the equivalent of their DNA."

"The fundamental things that make up magic?" Tony ventured.

Thor's eyes lit with appreciation. "Aye. Their magical DNA is eroding."

Tony nodded. "Like successive photocopies."

Thor frowned. "I do not understand the reference."

"If I take a document and make a copy of it, and then make a copy of the copy, and then a copy of the second copy, and so on," Tony said, "eventually, the copy will have degraded to be unreadable."

"Aye, an apt analogy."

"What does this mean for the elves? And wizards?"

Thor regarded him gravely. "Surely you've deduced that already."

Tony blew out a breath. "I was hoping I was wrong."

"You are not."

"So what do we do about it?" Tony demanded. "What can we do about it?"

"Mother believes a replication of the ritual that originally created them could reverse much of the damage."

Tony frowned at Thor's expression on the screen. "But she's not optimistic."

"To the contrary, Mother is extremely confident. I, however, am not."

"Why?"

"Because," Thor answered, "I've spoken with Sirius Black, Anthony DiNozzo, Louise Grant, and the Paddingtons. None of them were even aware of how the elves were created."

"That's not a statistically significant sample," Tony pointed out.

"No," Thor said by way of agreement. "But it does imply that the knowledge to prepare such a ritual may be … lost."

"And your mother can't find it? Or recreate it?"

"Perhaps, but 'twould be far less effective, mayhap staving off the inevitable only for another century or two."

"Damn." It was the least of what Tony felt, but if he let those feelings out beyond a single mild curse word, he might react like Hulk in Harlem. He shook that image away and regarded Thor seriously. "What do you - or your mother - suggest?"

"The Paddington family has offered to lead a research effort, to find what knowledge of the elves might be locked away in private family records or ancient archives. They warn this will not be a speedy task, but have offered their connections and knowledge for the effort."

"Good. That's - good." Not least because it was one less thing for Tony to juggle. "Goddamn wizards."

"Friend Stark?" Thor sounded puzzled.

"They go creating servants and then forget all about them. It's … disappointing. Infuriating."

"Servants?" Thor's eyebrows rose. "Nay - helpers."

This conversation was giving Tony a headache. "Explain the difference?"

"Helpers in magic. Creatures - our bodies are fragile."

Tony snorted. "Says the man who went toe-to-toe with the Hulk."

"Some less so than others," Thor acknowledged with an amused expression that faded quickly. "Beings, though - they can channel far more magic than creatures. They would've been necessary for any large rituals."

"Such as what?" Tony asked. "Nobody's talked about rituals."

"They have fallen out of favor. But as an example…" Thor paused, considering. "They might have raised any of your massive monuments. Or, mayhap, with sufficient warning, averted a natural disaster."

Or caused one. Tony didn't like the shiver than ran down his spine at the thought. He'd known magic was dangerous - hell, practically everything in the world was dangerous in one way or another - but this conversation had brought the dangers to the forefront of his thoughts.

"I - see."

Thor was quiet for a moment. "Mayhap you do."

After a moment, Tony said, "Let Sirius and the others know I'll help if I can. No idea how, but I will."

Thor probably didn't mean the incline of his head to be as regal as it seemed. Probably. And it wasn't because of that gesture that Tony sat just a little straighter.

"Thanks for the information," he said. "And thank your mother, too. It's not great, but it gives us a place to start. You staying in England for the holiday?" he added, more to lighten the atmosphere than out of any real curiosity on his part.

Thor launched into an explanation of a trip Jane Foster wanted to take to observe some unusual astronomical phenomena, and Tony wondered how he'd gotten so domestic in so short a time.