"There was a salamander thing and it shot drones at me and when it ran out it made the volcano erupt a bit more somehow, and like, there's people living on it, so I blew it up and it was a bit more explosive than I might have hoped."

"YOU DESTROYED DIVINE BEAST VAH RUDANIA?!"

"...I guess! I was afraid it'd hurt somebody!"

"That's..."

"INCREDIBLE!"

"I mean, TERRIBLE! The Divine Beasts were our last hope against Calamity Ganon! Not that I was getting much headway on the problem... nonetheless! This is a disaster!"

"How were they going to help, the flying one was full of that nasty goop. I was planning to just confirm he needs to be dead and then try exploding him too."

"We're pretty sure they shoot giant laser beams that scour the power of Calamity Ganon from the world! Or possibly they're just giant laser beams. They're not much help now, but they're also not helping Ganon much right now, so we could have turned them back to our side! Probably."

"Okay, well, I can make Sheikah Slates and they just appear without being charged for some reason, does that imply I can replace the salamander thing?"

"You make them? You made this?" He points at the Sheikah Slate. "Out of what?"

"Nothing."

"And you can make any sort of technology? That's ridiculous! And you can make another copy of Vah Rudania? But if it comes out dead, that's not very helpful, is it?"

"Yeah, how are these things powered? That's why I came to you."

"Energy doesn't come from nowhere, kid. Something small like the Sheikah Slate I can top up from the Ancient Furnace over the hill, no problem. It'll even recharge itself once you've got it going! An entire Divine Beast? When we dug those things out of the ground, we were afraid to touch them at first because our instruments were giving us impossible readings, so off the charts we thought one wrong move might blow half of Hyrule sky high! Which you apparently almost did!"

"Where I'm from energy totally does come from nowhere! I can make fully charged electrical batteries no problem. What's this running on instead?"

"Ancient energy. We still haven't fully characterized all of it's forms, but it's a family of degenerate structured-particle-automata in the conjunction of the aetheric, astral and mystic* planes, usually electroweakly confined along a material substrate. You're lucky most of the energy seemed to have overflowed in the aetheric when you ruptured the containment—no, not luck—how did you destroy Vah Rudania? The energy matrix should have vented four nines of the power as astral radiation when it failed! And speaking of astral radiation, JERRIN, DEAR!"

    "Yes?"

"RECONFIGURE THE SPECTROGRAMMETER!"

He rattles off a series of setting adjustments.

*closest mappings in English by connotation, but really their own names.

"I interpolated it - like this -" He does the sphere of wood into sawdust trick again.

"What the... is that atomized, or more or less fine—doesn't matter. If that's instantaneous, it'd have done it. Amazing! We thought the inherent safety of the power units was immutable, so simple and ingenious, but if all the crystal units were simultaneously discorporated..."

"So your furnace thing draws from these other planes that are full of magic energy and can charge things like that?"

"Approximately. Though it's not popular to call paraplanar phenomena 'magic'. I couldn't care less, but boy, you'd have ruffled a lot of feathers saying that around Magda back in the day."

"If I can't make it I'm inclined to round it to magic but if you say so. How's the furnace made?"

"I can see where this is going. First of all, an ancient furnace needs to be lit with an ancient flame to begin drawing power, and in fact it's terribly fiddly to calibrate and maintain! But second, you could tile all of Hyrule with ancient furnaces every mile, and you might be able to charge Vah Medoh to capacity in a year. It's a whole many orders of magnitude of difference! That's assuming you don't get slapped by diminishing returns when you try and do that, which you absolutely will, even at a mile of spacing!

"An ancient furnace isn't creating ancient energy: it's closer to condensing free-floating planar energies into pseudo-molecular structures we can utilise. Again, this space is very poorly characterized, but there are transport limits to the capture; it's very possible to extinguish a furnace by exhausting the local area—for example by landing a Divine Beast on top of it. True story! Now that's an idea—

"If you tiled Hyrule with Divine Beasts, each sparked to minimum power with a donation from one of the extant ones—they're much more effective at drawing power, we never figured out why—if you tiled the skies volumetrically with Vah Medohs—no, we'll get a lot of fantastic experimental data about the behaviour of the planes, but the transport factors are too steep. The density is self-defeating. Naively extrapolating, you might get a few Vah Medohs worth of total charge in a few months, but our models are useless at this sort of scale, and I'd bet you my forge that high-order effects make the yield even worse. Not to mention the potential consequences to ecology, geology and the fabric of reality itself! Uncharted territory, all of this.

"...okay, so how did they charge them in the first place? Did they just take a few years each?"

"I have no idea!"