Re. 4.2 I would say, well, that didn't go the way I thought it would - which is exactly what I thought it would do.
However it's close enough to build a theory that adds to the general picture so far of how Teyvat's fate system operates.
- In Teyvat fate is fixed
- this means prophecy is possible
- the overall story is about a bunch of factions trying to change the fate of Teyvat
- three Archon quests have been about it
- some other local (national) stories have been about it too (Scaramouche-Wanderer and René's doomsday cult).
- Descenders are people who can change the fate of Teyvat
- the end of the story will be Traveler re-weaving the threads of fate (says Dainsleif).
Well every story that talks about fate has to talk about changing it. But in Teyvat we talk about specifically what to do to change it. Typically an NPC will start off telling us that fate cannot ever be changed, and then they tell us about the exceptions. You can call the parts of fate which cannot be changed as "fixed points". So the art of changing fate consists of being aware of what is fixed and operating entirely without those areas to achieve your goals. I guess there are four examples, and they are (more or less in the order we're told about them?)
- Mona : You can change fate if it is to return to the "true path"
- Nahida : You can change fate if it's a small change, not a big change
- René : You can change fate if you have an external parameter to the world formula - aka a "Descender"
- Nicole : You can change fate if you stick to things outside of the gods' gaze
Now let's see how the prophecy of AQ 4.2 fits into this overall pattern. And by the way, Roozevelt beat me to the punch with this specific insight : namely that in the 4.2 AQ the fixed points of the prophecy are exactly equal to what is portrayed on the four slates. That is to say, the stuff on the slates has to happen, but anything else is up for grabs. Or in Nicole's terms, the gods' gaze is on those four events depicted in the slates. In fact it's hinted that some "Visionary" such as Barbeloth or Vedrfolnr (if they aren't the same person) must have created the four slates.
What does this mean? Well two of the slates are in the past, but this time our two different realities don't care about the past. We're not trying to change things so that Egeria never sinned in the first place. We therefore only care about the last two of the four slates.
These slates show:
- [slate 3] the Hydro Archon being put on trial
- [slate 4] the Hydro Archon suffering in loneliness
- [slate 4] a flood that reaches the Archon's throne
They do NOT show:
- what the result of the trial was
- people dissolving in the flood
So the entire bit of the prophecy about everyone dissolving --was incorrect. How did people start thinking that way? Furina makes it happen by deliberately putting out a lie that dissolving is part of the prophecy when it is not. We see this in game text. When Focalors (ie Furina's god half) preps Furina (ie Furina's human half) by wiping out her memories from when she was an Oceanid, when she was Egeria's familiar, when she became an Oceanid-human hybrid and when she became a god and Archon... all wiped out... but she inserts into Furina's memory the knowledge of "the prophecy". And part of that "knowledge" is the LIE that the prophecy includes making people dissolve into the Prmordial Sea water. it doesn't.
We know from the slates there's no dissolving prophesized. It's not Furina (before the split) that comes up with the prophecy. Furina (before the split) hears about the prophecy from Egeria. Furina probably knew all about the slates and might be the person who hid one of the slates. That's before the split into her two halves. She does this to make sure the prophecy is misrepresent as including "dissolving" when it doesn't. Furina (human half) becomes the main original source of this lie as she repeats it over 500 years. Not that she is aware that she's lying. Her old self (pre-split) made up the lie. Her divine half knows it's a lie. Her human self doesn't.
ETA: OK maybe I'm not explaining this clearly enough. She spots a small loop hole in the original prophecy - namely that dissolving isn't a fixed point but just heavily implied to happen because how else would all the other fixed points be achieved? Then she adds "dissolving" to the popular understanding of the prophecy to cover up the fact that this small loophole exists.
What does this achieve?
The whole objective of the plot is to switch out the non-fixed points of the prophecy as much as possible to avoid the bad stuff that "originally" was going to happen, while, of course, not changing the fixed points because they cannot be changed. What is changed from the "original" future history?
- the Hydro Archon is charged with fraud, not failure of duty to protect Poisson
- the Hydro Archon is found guilty and sentenced to death, not found innocent or otherwise left alive
- because Focalors is executed, Neuvillette gets his powers back
- because Neuvillette gets his powers back, he can stop Fontainians dissolving
How does Furina (before the split) manipulate events to get charged with Fraud and not dereliction of duty?
It's because Furina (human) is not a god and has no powers. Despite being told to act like an Archon, which she does for 500 years, and does well, in the end people close to her begin to figure it out. Not ordinary people, but people like Arlecchino, Neuvillette and the Traveler. If Furina (human) had managed to fool them completely this whole plot would fail. But she can't quite do it. And this is within the expectations of Furina (the god, before the split) when she made all this plot up. So Furina (human) is charged with fraud and is found guilty.
Why do the people who guess her secret get so desperate to push her to trial?
It's because they all are completely convinced that the people of Fontaine will dissolve in the Primordial Sea if they do not push her hard. And why are they so convinced? Because for 500 years the prophecy - which cannot be avoided - says it will happen. If the prophecy only said that the water levels would rise they could easily fix the problem just by evacuating people into boats. I mean sure they'd get a little wet and houses and buildings would be wrecked but people would have time to see the water levels rising and jump into the nearest boat. But they "know" that won't help because everyone knows the unavoidable prophecy says people will be dissolved.
Why does Furina (human) have to be kept in the dark?
It's not because Celestia has secret mind readers hidden in the crowd. That's not how any of this works. Celestia isn't even the proximal cause of the flood - the Whale is. The random Whale. Celestia put down the curse aka changed fate. Created the original prophecy and set those fixed points with their "gaze". They don't need to do anything else. There will always be a random Whale because that's how fate works. Even after the Whale is killed by Neuvillette some other random stuff comes up to flood Fontaine. "roiling energies" left over from the fight.
Because Fontaine flooding is a fixed point and is depicted in the 4th slate. So Celestia isn't monitoring the situation to make sure their curse works out. it's done. Fontaine WILL flood. As to how it happens? They don't need to care. Fate will figure that out. Some random thing will just happen, like a Whale. or "roiling energies". No matter what you do to stop it, something else just happens. Sound familiar? That's how it works when it changes the past too. Someone's got to kill those blacksmiths. Something has to break that vase. Random stuff is filled in by the fate system.
Furina (human) has to be kept in the dark about Furina's own (before the split) plot because if she was in the know she wouldn't be an emotional wreck. She wouldn't be lonely. She wouldn't be crying. She'd be happy. She's be joyful that she managed to rescue all the people of Fontaine. That can't be allowed because the 4th slate says the Hydro Archon has to be lonely and crying. How can she be lonely if nobody dies? By making her entire life for 500 years be lonely. In other words Furina's own plot (before the split) is to torture herself for 500 years so she has a near mental breakdown at the end of the trial, in order to fulfil the 4th slate despite everyone being saved, and to make Furina (human) is incredibly lonely despite spending her whole life surrounded by people who love her. The masquerade isn't to fool Celestia. It's to fool Furina herself (human part) to be lonely and sad at a time she ought to be rejoicing and surrounded by friends. (and to fool said friends into forcing her to a trial) Foclaors even admits a part of the curse was just there to make Furina unable to find happiness.
Why can't original Furina just tell Neuvillette to rig a fake trial after 500 years accusing her human form of fraud?
Because slate 3 says there will be a trial. So that has to happen. Now we're not told exactly how the prophecy was made but it's likely that under the "gods gaze" the Visionary could tell a real trial from a fake trial. So the slates aren't limited to mere visual information on what will take place. It's not enough to act out a fake trial (to fulfil slate 3) and act out the Hydro Archon sitting on a throne crying about being lonely and have a fake tub of water under it to make it look visually as if a flood is covering all Fontaine (to fulfil slate 4) . It's all actually got to happen. A real trial, with real stakes, brought out of concern for a real crime. Real tears over real loneliness and a real flood. Once you can fake all that you're good to go.
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The past isn't changed but we have two realities still. The original future and the new future. Hypothetically since we know that artifacts produced by Irminsul record the "original" or "true" fate of Teyvat before everyone messed with it.... I'd expect any hypothetical new artifact set covering these events to still record the "original" fate that had a ton of people dissolving.
In this respect changing the future is like change the past. Instead of history, it's changing "the history of the future".
