"So the sphinxes had... magic shortcuts, which they could only use indirectly, and the dragons had. The biggest R&D corner-cutting advantage ever?"

"There was something about self-healing, so it wasn't all indirect, but apparently."

"Well, indirect-when-offensive, I guess. What could they do besides that?"

"It doesn't say. This book has some very annoying informational gaps."

"How is it known that dragons were immune to harmful magic?"

"Apparently they got their hands on the diary of a survivor--a dragon-faction griffin survivor. He didn't know anything interesting about runecasting himself, more's the pity, but he had seen dragons brush off hostile magic like it was nothing."

"Any good primary source quotes?"

He flips to the relevant page and shows her.

May reads, murmuring softly: "My commander could in extremis write runes at random and speak to them as he would a soldier, trusting his touch to guide them away from unwanted magic; if his results were less powerful this way at least they took only moments to achieve, when we found ourselves without our preparations or references... Holy shit."

"I know. It's not anywhere near relevant yet, I suppose, since we don't even know if resurrection is possible yet, and even then finding someone who wouldn't just start the whole mess over again--I suppose just never resurrecting any sphinxes might do it, but I feel somewhat leery of choosing sides in this whole thing, even retroactively--but holy shit."

May blushes bright under her scales and giggles.

"That's--you--" he breaks off. "I am retroactively halfway worried about you. If a thing that everyone thinks is true were true then you wouldn't exist. I know it's irrational but my brain is screaming that you had such a close call--and oh my god this is going to be amazing, you can--" he breaks off again. "My brain is halfway screaming with retroactive terror and half with amazed delight. It is very confusing."

"If any historical event far back enough had happened differently most people wouldn't exist, you know. But - don't tell anyone? The way critters and medallions work there could easily be sphinxes the same way there's - me."

"...I won't. Although we might want to do less initial spellcasting in public. Especially if we're not as careful about checking the spells before we incant them."

"Yeah. ...And this means that if I test a thing the results are not necessarily reliable for you."

"Well, I think if it backfires it just doesn't work...?"

"Not necessarily. It might just - work and lack some side effect it would normally have. This also calls into question the 'can we just not intend to cast and therefore not cast' result, I was the one who tested that."

"I didn't bring the wax tablet again, but I can try not-intending-to-cast when I get home. And...don't scribble runes at random, I guess, but as long as we don't completely neglect double-checking things I expect we can probably prevent serious unpleasant side effects."

"Or just have me be the one to cast anything questionable."

"Or that, yes. If it turns out I can refrain from incanting while technically saying the incantation, it might be worth checking to see if you get any feedback when you negate a magical effect."

"Yeah. And I think I'll just practice with, like, suppressing a cheap luck charm while rolling dice, in case my powers have been exaggerated or it varies individual to individual."

"Yes, it's probably a good idea to make sure the dragon from the diary wasn't some kind of miraculous prodigy before doing anything really dangerous."

"Or a different kind of dragon or something. I think there used to be all shapes and sizes and colors. There's kinds and kinds of griffins, you can barely tell nemean and bohemian lions apart..."