TL:DR

This is a post I have been wanting to make for a very long time now but I kept running into roadblocks. With the parallels between the characters growing more each patch, it’s gotten a little easier to write so this is my attempt to share some of the parallels I have seen between four characters: The Celestial Emperor's Daughter, Koitar, Fischl, and the Tsaritsa. 

For those who may be a little newer to lore, the Celestial Emperor's Daughter is canonically Princess Fischl. These two are the same character but the story is told differently between two books.

https://preview.redd.it/05qhuak9qmhh1.png?width=1109&format=png&auto=webp&s=db5e2738214399835ca078010b37d053bd1be028

Koitar and the Tsaritsa are the speculated parallels for the Celestial Emperor's Daughter and Fischl. In my personal opinion, Koitar would be the romantic parallel more closely tied to the Celestial Emperors Daughter, with the Tsaritsa more closely paralleling Fischl. But again, since Fischl and the Celestial Emperors Daughter are essentially the same character, there are some parallels between all four. 

For some of the information on Fischl you will need to have either played or read through the Immernachtreich Apokalypse event back in 2.8.

Let us begin.

The most obvious parallel between these four figures is their royal status. The God King [Celestial Emperor] refers to the Celestial Emperor's Daughter as the Prinzessin der Verurteilung after forging her as the final Divine Halberd.  The Morning Star is attributed to Phanes, and Koitar is the Princess of the Morning Star. Fischl is the daughter of the "Kaiser and Kaiserin der Verurteilung," and while it's never stated outright, Fischl's father is described as "not a mere shade," which is likely another parallel to Phanes. Even though Tsaritsa's parentage remains unknown, (we only have the name Feodor available right now) she is the "Tsaritsa" which is an Empress.

Each of these characters have a devoted companion/guide. The Celestial Emperor's Daughter is joined by Mir, who slays any demons they encounter. Koitar has the Voyager who was her "sword, shield, guide, and unpardonable conspirator in rebellion." Fischl has Oz with their bond being described as having "a shared soul and fate" and they are destined to meet. The Tsaritsa's companion would be Pierro who Childe describes as "the first ever Fatui Harbinger."

The Celestial Emperor's Daughter and Fischl both literally share their companion's vision. The Celestial Emperor's Daughter temporarily takes hold of Mir's eye, and Fischl has the ability to see through Oz. I could not find anything to directly link Koitar seeing through the Voyager so it may just be metaphorical describing them as having the same goal. For the Tsaritsa, a good friend of mine [who has theorized the Tsaritsa was Fischl for years] pointed out this piece from the Gods Limits trailer that may hint at Pierro having a “gaze of the deep” similar to Oz:

Whose gaze could pierce this far?

Their goals are all tasked differently, but they are all driven by the same desire to save humanity by fundamentally changing the world. The Celestial Emperor's Daughter goes on a journey to recover fragments of the Divine Halberd [Ominous Swords] to prevent the world's destruction. Koitar rejects Phanes order and vows to "recast absurd laws" to build a new world where humanity is finally free from its "shackles" which I feel mirrors Fischl's "May my people be freed from the shackles of ancient decrees." Fischl's destiny is also the world's renewal as at "the end of karma itself she will gather every soul and cleanse the world of all that is ugly and wicked." The Tsaritsa has a similar goal, which will somehow be accomplished with the collection of the Gnoses. Again, we don't have much on the Tsaritsa, but Pierro says the Tsaritsa seeks to "cleanse the sources of distortion in this world: short-sighted, ignorant gods and the darkness and corruption of the Abyss." Despite the differences in their methods, they are all characters who are tied to the world's salvation through the overthrow of the existing order.

https://preview.redd.it/fueqrsacqmhh1.png?width=1330&format=png&auto=webp&s=fbf3e3351c528f0b1dea12e6edd7fe62b59e61a3

The last parallel I want to discuss is the theme of having lost or forgotten something, and there being an expected "return" after remembering. Koitar was stripped of both name and form and has a storyline of her followers hoping to "return to the majestic golden city." Fischl has a similar storyline regarding a lost homeland with followers waiting to return to it, but her realm is prophesized to return when she regains the memories of it. After the Immernachtreich fell into darkness hundreds of years ago 👀, an ancient prophecy foretold that Fischl would one day "regain the forgotten memories of the paradise of the Immernachtreich" and the kingdom's promised future would finally come to pass. While we do not know much about the Tsaritsa, I did find something that shows a possible parallel. Pierro says the Tsaritsa will "once again be a god who loves all humans and in her ideals shall all human wishes be granted," which could imply she needs to fulfill something in order to return to her "true self," just as Fischl and the Celestial Emperor's Daughter do. We already knew from Venti that the Tsaritsa had a shift in demeanor after the Khaenri'ah disaster hundreds of years ago 👀, but this was all I could find that may hint at a future parallel. [Just as a side note, the Celestial Emperor's Daughter does say she has "forgotten her name," but Mir suspects she says this because knowledge of a deity's true name allows a human being to exercise absolute control over them. So it is being omitted for now.]

A dream yet to be dreamed?

Since these characters parallel each other in many ways, I wanted to see what predictions can be made for the future story. 

Theory area

Fischl's Immernachtreich is Koitar's Hyperborea and Tsaritsa's Khaenri'ah.
Fischl's Immernachtreich appears to fulfill the same symbolic role as Hyperborea and Khaenri'ah: a homeland where those who forsake the existing world can gather. Koitar has a dream of a future where humanity stands alongside the gods they once revered; where there is no more tears, sorrow, or death because all has finally been made complete. Fischl creates a world by weaving the power of "darkness and dreams" and then calls her people to migrate to the Immernachtreich, promising that "so long as her heart beats she will never forsake them." Again, we do not know much about the Tsaritsa, but I feel this is echoed in the Long Nights Artifact set that says the Tsaritsa declared that even those living in the "borderlands" remain children of the motherland, "for in her boundless love, the Tsaritsa abandoned none who chose to follow." With the reveal that she is related to all Khaenri'ahns, and all the Khaenri'ahns that follow her, I think it could be that Khaenri'ah is the Tsaritsa's "Immernachtreich," or it is at least a "branch" of it.

I highlighted this section from Fischl's Character Story 3 in the Megathread after the devs lore-nuked us during the livestream and wanted to share it again for anyone who missed it. My friend pointed out to me a long time ago that this can be read as the Tsaritsa and Pierro in Khaenri'ah during the Cataclysm. This is Fischl and Oz's first encounter.

• When the lone pilgrimaging princess reached the kingdom of eternal twilight [Khaenri'ah], the fate-resisting royals chose to deny everything in their desperation. They refused to recognize Fischl's noble stature and mission as the princess of the Immernachtreich; denied their 13,000-year lineage as a branch of the royal family; and forsook their own nobility and restraints as humans... devolving into clumsy and vicious beasts.  In the palace of Twilight and amidst the teeth of the beasts, the princess shed her sacred blood on the ancient emblem. At the moment of her peril, the dark wings of the night ripped the trapped, wounded princess from her despair and took her under its wings. Following the scent of her noble blood, Ozvaldo Hrafnavins, the King of Ravens came to the princess and pledged his eternal loyalty.

Please note the Fatui Leitmotif 🎭

This one is going to be bold so prepare yourself. I believe the Tsaritsa may want to destroy the Vision system.

Zhongli is still on the chessboard with Tsaritsa in the Snezhnaya preview and we know he made a contract with the Tsaritsa of some sort. The only thing he said about it was that it is the "Contract to end all Contracts," but his Gnosis character story adds a detail: "And for the God of Contracts, who must have established countless such agreements in his long years of existence, such an important contract must have come with its benefits." While trying to see what "contracts" could mean in this context, I came across one of Zhongli's voice lines: "Visions are also a type of contract. You should know that all power comes at a price. For every bit of power you gain, so too do you gain more responsibility."

The entire vision system was created as a "new order" to maintain Teyvat after HP had their functions ruined during the War of Funerary Flame. Archons are duty-bound to impart part of their elemental mastery to whoever is designated to receive a Vision. In return, the gods receive a gift "more abundant" once the Vision bearer has "completed their duty." Since archons are themselves "shackled" by this obligation and every bit of power gained causes more responsibility, it could be the benefit for Zhongli is having his "shackle" broken.

Visions result from the system that used the Third Descender to create the seven Gnoses as a means to consolidate the archon system. The latest lore we got from Sandrone informed us that since Visions come from that same system, the manifestation of a Vision is "to some extent" related to the Third Descender. If the Tsaritsa is indeed tied to the Third Descender in some way, then this could provide another reason for why she seeks to destroy the Vision system.

With all that in mind, and as outlandish as it sounds, I think it's possible that the "Contract to End All Contracts" is literally a contract to help her bring an end to all Visions: the contracts that binds archons and humanity. Not sure what that would do for gameplay 🙃 but we are supposed to go to Khaenri'ah next, and there will be no Vision holders there anyway lol

Quick call outs that don't really fit anywhere else

• The Fatui face the world from behind their masks because all they once were mean nothing once they become Fatui, and thus must they forsake their true names and faces alike. This could be what Koitar is doing as "Anastasya" if she is actually Koitar.
• Fischl's theme, Sieh an, mein Sommernachtgarten!, has the Fatui leitmotif.
• Fischl played the part of the Fatui who stole the Lyre in the Echoes of Memory event.
• Rule of Three: you must first overcome three difficulties to succeed on your fourth attempt. 🤗

That's all the information I can put together decently for now. If I remember anything else later, I'll come back and update this post. I've been working on this post for a while now and it's gone through quite a few revisions, so if anything feels unclear or doesn't flow very well, please let me know. I'd be happy to clarify or elaborate :) Sorry for such a long post, I hope I gave enough image breaks!

And of course, a post about the Celestial Emperor's Daughter, Koitar, Fischl, and the Tsaritsa would not be complete without the following:

Face this false world with pride, my daughter. Enact the 'truth' within your heart —Flowers for Princess Fischl - Final Chapter: Princess Tears and Sinful Saints

Next patch, we get dialogue from the Moon Sisters explaining why they took on human forms. It seems they did so in order to visit humans "on the surface." There also seems to be an attempt to address why the Moon Sisters allowed the Heavenly Principles to overthrow the dragons and reshape Teyvat. [a poor attempt imo 💀]

• Canon: "Ah, Aria. It seems you've already chosen a "human" form for yourself as well."
• Aria: "That said, I didn't expect that you would proactively create such a form for those lovely little beings."
• Canon: "It is only natural, Aria. Those fragile lives trust me and call out to me, so I shall respond to their voices. We were born to preserve the world. If the beings known as "humans" are willing to settle it, listening to their pleas also fulfills the mission our King bestowed upon us...
• Aria: "Yes. After all, he did say that all life across the sea of stars are allies. They fight alongside us against the darkness. But I wasn't talking about that. I mean, I didn't expect you, the "Frost Moon," to have such a sentimental side. It's very cute."
• Sonnet: "Sisters, now that we've shaped bodies for ourselves, shouldn't the first thing we do be sneaking out to have some fun with the people on the surface? Otherwise, we'll have made them for nothing! Hurry, before anyone discovers us—"
• Aria: "Why, I remember that when they first started building their civilization on the surface, you even said, "That outsider is bad news, and naturally, its creations are the same." You wouldn't even spare them a glance."
• Sonnet: "I still think you two shouldn't have let that outsider in, but the people on the surface..."

We also get some Istaroth sus crumbs

• Canon: "That Descender's servant said they had matters to discuss with me about this world's gravitational potential and metric tensor {laws of time}. [Istaroth] perhaps it's just my imagination, but I have a certain... feeling about how she views that Descender... I won't jump to conclusions, Aria. But I'll keep an eye out."

One of the locations on the moon is the Golden Hall; I came across this text and think maybe it will be in this area somewhere.

• I am Euthyphro, hailing from Arcadia, the eternal holy city.
• O Mother of the silver shuttle, the ever-blessed goddess Prusmene, by thy grace, I take up this meager quill to chronicle the night's final splendor.
• I beseech thee: grant me once more the hallowed gift of inspiration; preserve thy devout believer, lest my soul descend beneath the silver tree, to be sullied by the dust.
• O wise and radiant queen, bringer of the light! I beseech thee: deliver thus thy devout believer; That my mortal frame may find eternal rest within thy holy embrace.
• O wondrous Prusmene — ancient mother of the night and daughter who brings the light, mistress of the Golden Hall! Countless times hast thou guided my vessel, permitting me to usher unsullied souls unto the lunar palace above the clouds.
• Thou grantest mortals slumber within thy pale embrace; thou grantest them dreams that are theirs, and theirs alone. Yet this is to be the final night — the final rest. For there sits the eternal throne in the heavens, the Primordial One, O world-shaking lord!
• It forgeth the bones of the earth. It biddeth all dreams return to the earth, and all dreamless things to return to the earth. It seeketh to shroud the dreams of man with its own dream, that we, the mortals of this fleeting world, shall abide an age without beginning or end, passing through a life of tranquil, dreamless rest.
• O wise and radiant queen, bringer of the light, deliver me from the hands of my dread master! For thee, I have ushered the unsullied souls. For thee, I have steered the great and silver-shimmering vessel.
• I beseech thee: deliver thus thy devout believer, that my mortal frame may find eternal rest within thy holy embrace!

As you all probably know, next patch we are going to the moon. I have been digging through the text map over the past few days and want to share with you all what I have found 😄

These are some of the important NPC's.

• Ungien - a researcher in the field of life sciences. Pupil of Ibni-Belum
• Maagees- Ungeins wife, an expert in life sciences, a professor. Also known as Researcher Maagees-Geti 
• Lusalim- Ungien and Maagees' student.
• Ibni-Belum- the first Moongazer [I think this might be our glorious king Nibelung]
• Ninnin/Eggie->! Lusalim's daughter. !<

I tried to piece together the story as best I could. The information in bullet points is text from the text map.

TL;DR at the bottom.

I think Ibni-Belum might be Nibelung, it relies on the spelling in CN text. CN text uses 尼伯龙 for Nibelung [if I am not mistaken] and Ibni-Belum in CN is spelled 伊比尼伯龙. Adding a dash before the name Nibelung in CN gives you 伊比-尼伯龙, which then translates to Ibi-Nibelung; this could of course just be a coincidence and I am not a CN native but wanted to mention it. [Edit: it seems this is just a coincidence for now 🥀]

• "It starts with a dragon pioneer named Ibni-Belum {the first Moongazer}. The lunar vessel we traveled in was his creation. He was the one who led dragon researchers to the moon. After the pioneer landed he began to explore the moon and circumlunar zone. Then, one day while in the circumlunar zone, he received a mysterious signal from deep space. The researchers couldn't decipher the signal's meaning. But the pioneer believed it was a message sent back by their [glorious] king who had journeyed out into the sea of stars, and that [glorious] king's name was Nibelung."
• The pioneer Ibni-Belum once proclaimed to the researchers who had set foot on the moon: "The sky of stars above our heads was born not of the King's dreams. It hath ever been there, mysterious and silent, awaiting the day its children would look up in curiosity..."
• "My pupil, Ungien, is a rebellious, obdurate mule who respects neither teacher nor king. Were his talent not sufficient to overshadow his flaws, I'd have booted him off the moon by now." Design and Engineering Resource Support: Ibni-Belum.
• Phase II retrofitting of the orbital positioning facility in Nephilheim —constructed by Moongazer Ibni-Belum, hereafter referred to as "Engraving" — is complete. [...]...The original "Engraving" has been reinforced. Countermeasure testing against (...) and (...) weapon systems has concluded. For detailed records, refer to the appendix. Despite its original design intent, the facility is capable of serving as an emergency bunker...Supreme glory everlasting to the Creator!🙌🙌🙌

Ungien, a life scientist, believed that among the stars live many mysterious creatures not yet discovered. He believed that a deep-space signal received by the dragons was not a message their [glorious] king had sent back, but rather it came from some mysterious creature from beyond the stars. To that end, he built a capture station in the space above Ungien's Circle on the moon.

He chose to pilot a spaceship named Moongazer "Because he wanted to overturn Ibni-Belum's theory." He returned with Black Stellar Energy which he began to fuse with. After Ungien fused with the "Black Stellar Entity," his body also began secreting the same substance across its surface. Maagees named it "Blackbody Matter."

• Ungien's wife, Maagees, was the first to enter the spaceship, but she only found a round, black, spiky creature inside..."
• "The black, iridescent filament-like ejecta found on the outer hull of the "Moongazer" possessed a unique "reflective" property. This likely explained why the spaceship remained concealed..."
• "The ship's log showed that the creature emitting the signal didn't attack Ungien. Instead, he was the one who chose to fuse with it..."
• "Maagees ran a series of tests and thus discovered that her lover was fusing with some unknown creature."

Ungien passed on a message to the dragons. After delivering the message, Ungien began to die. But Maagees, used an experimental technique on him. Ungien's consciousness was completely lost during this process.

• "Day 37: The Eye of Ibni-Belum team has decoded the vibration frequency. To our surprise, it was a message in our language. Roughly translated, it reads: "I'm glad this message reached you." Ungie... Is that really you? What are you trying to tell us???"
• "But then she showed me the entirety of the message brought by the Black Stellar Entity. It was only then that I finally understood what she had been reaching for."
• "Day 98: Phase I experiments confirm that pure energy increases blackbody matter activity, and in particular, the Archaeolune Energy contained in biological organisms produces a stronger response. Ungie, maybe this is why you ended up like this. That thing you found, it thirsts for our bodies."
• "Professor Maagees has successfully operated on Containment Object-1 using an emerging, unproven biotechnology. She has managed to turn it into something completely new — a living being that is the total fusion of Archaeolune Energy and blackbody matter. That little onyx creature grows larger with every passing day. Maybe one day it will be even larger than the sky itself. But we all know that no matter what it becomes, it will never be the Professor Ungien we knew..."

Maagees requested that her student [Lusalim] use the same technique on her, ultimately being converted into a new lifeform. Just as with Ungien, her consciousness was not preserved.

• "Today, I shall bid farewell to Professor Maagees. In accordance with her wishes, I shall perform that operation of creation on her later today, just as she once did when she created Ungie. This is something I have to do myself, for it is what Professor Maagees wants. The experience I gain from the operation will be vital to the upcoming Project Moongazer, particularly to the work of creating life itself. This is also in line with King Xiuhcoatl's wise counsel. For so long, I believed her insistence on sending that message was simply grief turned into obsession, the fixation of a human being who had lost the one she loved." [I'm not sure why the word human is here 🤨]

these two entities might be Ungien and Maages

Maagees and Lusalim worked on Project Lunar Veil to make a veil that could obscure the moon. Lusalim eventually gave the research for veil building to the usurper. [BOOO 🍅🍅🍅]

• "Still, Professor Maagees agreed, so we proceeded with it. When she asked me for a project name, I suggested "Project Lunar Veil" — a veil that could obscure the moon."
• "Lusalim successfully experimented with a miniature Lunar Veil by applying it to Ungien's Circle..."
• "Records Regarding "Project Lunar Veil: Phase I" Phase I was a success. We created a miniature Lunar Veil to shroud the biosphere, but it only made me more anxious."
• "And that final step is — life, information, and memory must be given a way to be inherited and to circulate. The power of the moon's origin, granted to us by the Moon Goddess, is enough to make this possible. I will not see the project completed, for I have sinned against dragonkind. I capitulated to that terrifying sovereign who was not of this world, and surrendered the precious results of our research. I do not intend to escape judgment."
• "That is why I now entrust Project Moongazer, now only one step away from completion, to you. And that final step is — life, information, and memory must be given a way to be inherited and to circulate. The power of the moon's origin, granted to us by the Moon Goddess, is enough to make this possible."

This is what I found so far related to "Blackbody Matter" research. My takeaway is that the veil is made of Blackbody Matter mixed with some sort of life. The mini veil made by Lusalim worked when applied to Ungien's Circle which is a realm of life.

• "I must therefore devise a safeguard, and the key lies in the properties of the Blackbody Matter..."
• Day 1: The surface of Containment Object-1 is glossy black. Its morphology remains indeterminate and exhibits irregular wave-like fluctuations. Tests produced no response to auditory, visual, or physical stimuli. No food or water intake was observed today.
• 30: Containment Object-1 vibrated at a high frequency when shown starfield footage with visible celestial bodies for around ten seconds. The corresponding frequency band has been entered into the spectrometer.
• Day 98: Phase I experiments confirm that pure energy increases blackbody matter activity, and in particular, the Archaeolune Energy contained in biological organisms produces a stronger response... Ungie, maybe this is why you ended up like this. That thing you found, it thirsts for our bodies...
• "Experiments have revealed that Blackbody Matter can mutually stimulate with Archaeolune Energy, and can also fuse with plants and animals. In some fused specimens, coloration shifts from blue to black."
• "The ecological research team has cultivated thousands of Moonshade Trees. From among them, Professor Maagees's team selected compatible specimens with a high compatibility for integration with the "Blackbody Matter."
• "A Moonshade Tree, shaped through selective gene tuning, spreads its branches wide. The blackbody matter it emits can form a vast screen, shielding this place from prying eyes and hostile observation."
•  "It is truly astonishing. When we were testing the "Curtain-Form Blackbody Containment," Ninnin could barely even speak.

I am still going through text map so if I find anything else I will just edit and add what I found here. Even through all of this I still cannot judge the timeline for all of this. I think it is before HP arrived but Lusalim gave HP the blueprints for a veil; yet Lusalim does not refer to HP as "usuper" and called them a '"terrifying sovereign." Not sure what to make of it, maybe it was during the war before HP won 🤷‍♀️

TL;DR

• A dragon went into space and came across black matter and fused with it.
• Experiments lead to the discovery that Blackbody Matter has the ability to fuse with plants, animals, and led to the development of engineered Moonshade Trees. Coloration shifts from blue to black.
• “Project Lunar Veil” was started and the matter was formed into a giant “curtain” or “veil." Dragons figured out how to create an artificial sky/veil using blackbody matter and living organisms.
• Lusalim eventually handed the veil over to HP which is considered a betrayal.
• Teyvats firmament is likely a fusion of blackbody matter, memory, life, and biological networks.
• Phanes likely reshaped Irminsul to power the veil thanks to the dragons research.
• Ibni-Belum might be Nibelung, the first moongazer.

Edit: most of the quest is out now. Correcting and adding info.

- "You fail to stop the self-destruct sequence, and as the countdown ends, the base is engulfed in roaring flames. The good news is you manage to escape the explosion unscathed with Paimon in tow. But alas, the mysterious black kuuhenki, the spaceship bound for the moon, and the tale behind them all vanish from your journey forever."

- Mysterious Kuuhenk-"Columbina... rescued me... on the moon...When I woke up... I was very weak... I forgot... many things...She took me to... a place of healing...It was called... Silvermoon Hall..."

- Black Egg: "Knotted Moonlight Vines... They grow in places where the ancient moon's power has been thrown into turmoil... perhaps that's why..."

Areas

- Ungien's Circle: many species of creatures live there; it is a home for living beings.

- MoonGazer Tower: The researchers could not enter deep space so they built this tower after receiving a message from deep space.

- Moonheart: Endless energy is drawn from the Moonheart, fueling the ancient dragon's ascent to the heavens.

- Eye of Ibni-Belum: A lunar surface monitoring station, capable of monitoring the entire lunar surface. The Eye was originally a deep-space signal transceiver station built to recapture the signal recieved from deep space. Many years went by, the pioneer passed away, but the signal never appeared again. His students gave up years later and turned to more practical pursuits. They renovated the Eye into a lunar surface monitoring station to make it easier for them to conduct more practical lunar research.

- Ab-Irimu Storage Array [No. 59]- This array is primarily used to regulate the operation of the Engraving and to store various research resources.