@abyssalprincess27 submitted: Small brown moth found in Redmond, Washington, USA during the day, in late summer!

The Fatui's rulers, the Harbingers, monitored Diluc's progress from the shadows. The prowess with which he laid waste to numerous Fatui strongholds caught their attention and forced them to take action. Diluc narrowly escaped death at the hands of the Harbingers thanks to a third-party observer from the north, who was part of a vast underground intelligence network. The observer claimed to have been watching Diluc for some time, and approved of his methods. After his close encounter with death, Diluc took a long hard look at his past and the anger he had harbored for so long. Acknowledging his shortcomings, he decided to join the underground intelligence network. Just like when he first joined the Knights of Favonius, Diluc committed himself fully to his work. His talents and skills saw him rise steadily through the ranks into the upper echelons of the network. The network was made up of volunteers, and many of its members had willingly given up their prior positions and reputations to join. Some had even abandoned their names. Diluc - Character Story Four

I've long wondered what this third-party intelligence network in the north could be. For a while, I considered the Treasure Hoarders the most likely group, because of the way Kaeya uses them for intelligence. But after the On The Trails of Behemoths event, I'm convinced this group is one in the same as the "organization whose details may not be disclosed" the Traveler gets commissioned to collect data for in the event.

[This could be the Voynich Guild- Paimon's line about Helka's practice of note-taking certainly matches the famed Voynich Manuscript. "Speaking of, you were taking all those photos and drawing in your notebook while (Traveler) was fighting. It all looked pretty professional!" But for the sake of the post, it doesn't matter.]

Mavuika acquires 'intel' about the phenomenon in the sky seen above the Stadium of Sacred Flame.

"Such fragments are known as 'Ancient Moon's Remnants,' relics of Secret Source technology from the era of the Ancient Dragons. Coincidentally, a small squad of Fatui infiltrated our borders around the same time it appeared. Our investigation revealed them to be the subordinates of The Doctor. Their stronghold is in Nod-Krai, a land with a long history not far from Snezhnaya. The people there can use a very special power. It is said that this mysterious power predates even the seven elements of Teyvat."

Now, I want you to recall what phlogiston is. Yohualtecuhtin, Lord of the Night says, "Phlogiston is Teyvat's primordial form of energy. The Heavenly Principles used phlogiston as a basis for the creation of Elemental energy... to develop a power to better counter the Abyss." She continues, relating to the Light Realm and Human Realm, "Light refracts into seven different colors, which we collectively refer to as a rainbow. Elemental energy is a similar concept. It's essentially the modern counterpart of Phlogiston…"

We know from the AQ that the Fatui have been covertly researching phlogiston when we raid the Phlogiston Extraction Research Center, and it doesn't seem likely to be Capitano at the head of this. It might be Pantalone- Citlali's SQ shows that Fatui under him are active in Natlan- but I think it's Dottore, matching what Mavuika mentioned regarding the Ancient Moon's Remnants.

What's the primordial sea then? The Lethe to our Phlegesthon? The "cosmic ocean" mythological motif is known to frequently feature the struggle between fire and water, so primordial seawater may only be half-made of our water equivalent. In the "Diary of a Soldier Abroad" we find in the Phlogiston Extraction Research Center, we see our soldier contrast boring phlogiston with Fire-Water; clearly, this is meant to be vodka, but it might make an interesting allusion.

Dottore & Phlogiston are connected. Dottore & Nod Krai are connected. Diluc and Nod Krai are connected. Before I string these all together, let's talk about Divine Nails.

Divine Nails are dropped by Celestia to purify Abyssal corruption, as evidenced in the lore of the Staff of the Scarlet Sands, the Amethyst Crown, and in Nahida's SQ. She says they have "the ability to purify and stabilize powers that shouldn't exist in Teyvat." and speaking on the Oozing Filth, says "Forbidden knowledge that its light has shone upon is kept here forever in a different form…"

Let's keep track of our motifs here- this is Dvalin's tear before and after the Traveler purifies it.

There's the Statue of the Seven before and after activation

We have Deshret's Primal Embers and Primal Torches

Then there's the Lumenstone, and the Oozing Concretion.

"What flows within this nameless, voiceless azure crystal? The secrets of the heavens? Or the whispers of the abyss?" - Lumens: Stone of Light

The Chinese name for the Lumenstone shares the name of Pyroxene, a real-life groups of minerals whose name means "fire-stranger", named for their tendency to appear as impurities within lava.

(the Lumenstones, while purifying, also drive miners insane. Remind anyone of a certain mad someone?)

When it comes to the Canned Knowledge Capsules, which vary in colour based on their amount of elemental energy, the purple ones give off no such elemental signature. We also see that the Court of Desolation contains the same mud as the Chasm.

"The Abyss manifests its power in a manner that is most devastating to the place in question. In Sumeru, it was forbidden knowledge. In Natlan, it was monstrous creatures." —Nahida: About Haborym

I believe that there exists a delicate balance of the "red" substance, phlogiston, and the "blue" substance we see in Divine Nails. When they're out of balance, the "red" and "blue" give us a corrupted "purple". Think the defiled statue, or the tainted blood on Dvalin's back.

And then think of Elynas' heart; Elynas' brother, Durin, also has a warm, red heart, and it's possible that other corrupted, Abyssal-adjacent dragons like Ursa the Drake have it too.

Dottore and the Delusion

Krupp, adjutant of Dottore in his posthumous robot form

Il Dottore has two major motifs; the plague doctor's mask, and the vial.

I would focus on the blue vials, which are present in both the manga and the current game. I contrast them with the red eyes he and Krupp share.

His goal in Mondstadt at the time of the manga is still being theorised on. On the surface, he seems to be only vaguely interested in using Mondstadt as a source of human test subjects, before turning his attention to the strange power displayed by Diluc. He has his subordinates attempt to capture Diluc, but they fail, and that's that.

The subtext is deeper.

He's likely the one who orchestrated the death of Crepus Ragnvindr, using his birdlike devices to draw the ire of Ursa the Drake, forcing Crepus to use his Delusion (which then backfired on him). He may have made one of his segments take the place of Eroch at the Knights of Favonius, a traitorous figure who contributed to Diluc's radicalisation against the knights. (We know Il Dottore can change his appearance from The Night-Bird Falls at the Curtain's Call)

[I think it's possible that Il Dottore is using Ursa the commit the sin of influencing human evolution, just as Jakob Ingold and Rene de Petrichor used Elynas.]

Now let's talk about Crepus' Delusion

It's different from every Delusion seen thus far. The case is unique- perhaps being the Nod-Krai-specific case- and the symbol it shows is not the Fatui insignia. In fact, it resembles the alchemy crafting bench's possible representation of the planet Teyvat lies on and its three moons.

Alice even uses a red version

And it doesn't seem to utilise the elements, but a purple-black fire reminiscent of the Oozing Mud.

This power could relate to the Frostmoon Scions of Nod-Krai

The inspirations are important here- Genshin's phlogiston is based on the real-life theory of phlogiston developed by 18th-century scientist Georg Ernst Stahl to explain combustion. In his time, oxidization were not understood and chemistry operated on an alchemical model. Similar to Genshin's phlogiston, Stahl's theory gives a solid and liquid form to the earthy substance phlogiston is paired with- terra lapidea (stony / rocky earth) and terra fluida (liquid earth), with terra pinguis (oily / fatty earth) being the combustible fire element that escapes into the air, visible to us as flame.

But as chemistry advanced, this theory was supplanted by oxygen theory.

In 1766, Englishman Henry Cavendish isolated a gas that he called "inflammable air" because it burned readily. Priestley noted that when inflammable air and common air were ignited with a spark in a closed vessel, a small amount of "dew" formed on the glass walls. When Cavendish repeated the experiment, he found that the dew was actually water. Cavendish explained the results in terms of phlogiston and assumed the water was present in each of the two airs before ignition. For Lavoisier, combustion meant combining with oxygen; however, until he could explain the combustion of inflammable air, some would still doubt his new chemistry. In June 1783, Lavoisier reacted oxygen with inflammable air, obtaining "water in a very pure state." He correctly concluded that water was not an element but a compound of oxygen and inflammable air, or hydrogen as it is now known. To support his claim, Lavoisier decomposed water into oxygen and inflammable air. Now that the composition of water was known, the last objection to discarding phlogiston could be eliminated. - The Chemical Revolution of Antoine-Laurent Lavoisier

The disproving of phlogiston theory is tied directly to the discovery of the composition of water; of oxygen, and hydrogen. The fiery, reactive element and the watery, inert element. In fact, our real-world understanding of hydrogen as the "first" of the elements mirrors Genshin's phlogiston which refracts into the seven elements of Teyvat. The simple structure of the hydrogen atom and the spectrum of light produced from it or absorbed by it helped us understand the atomic structure of our world's elements.