The 8th umbral calamity

[Lyth]

Ah, I think I see part of the confusion here.

The shards themselves are more akin to 'parallel dimensions' than 'parallel timelines' (think more Chrono Cross than Chrono Trigger). When Argos sunders himself, he produces multiple identical copies. The same is true for the shards of Etheirys, except that their histories diverged about twelve thousand years ago, such that there are similarities and differences to each. For example, Norvrandt, the part of the First that survived the Flood of Light, is essentially just Eorzea. Eulmore is Limsa, Rak'tika is the Shroud, Amh Araeng is Thanalan, Il Mheg is Ishgard, and Lakeland is Coerthas. There are differences of course, to account for our different histories. Midgardsormr used to sleep by the aether rich waters of Lake Silvertear, entwined with the wreck of the Agrias. Bismark instead sleeps in the aether rich waters of the Source on the First. There's very much a 'Light World'/'Dark World' vibe in this. I'm pretty sure that I turned into a rabbit when I first arrived in the Dark World.

How the shards influence each other hasn't been clarified yet, but that's the really interesting part. The main relationship between them is likely the lifestream. Why is it, for example, that an event that wipes out all life on a shard causes a rejoining? If the lifestreams are all connected, then perhaps the souls all just migrate back at the same time, the force of which pulls the two shards together. There's also the question of how the elemental alignment of the shards are linked. For example, Mitron explains that when the Ascians brought about the Flood of Darkness and transformed the Thirteenth into the Void, the shard that was most influenced by this was the First, which strongly shifted its polarity towards the Light. Which is why the First is actually the Shard that the Ascians were trying to rejoin for the longest. So why is it that the First and Thirteenth have such a close relationship in particular? And if so, what other pairs of worlds have a similarly close association?

This is the sort of thing that I really want to understand with regards to this game's dimensional travel.

The timelines are different in that they represent 'possibilities'. So each timeline in which the sundering exists should contain the various shards simultaneously. When Dayan meets Mide in the mathematical simulation generated by Alexander's core, he explains that Alexander's creation generated an infinite number of potential futures separated by 'nary a thread'. Each one represents a potential outcome across all the shards. In one of them, for example Alexander prevents the Seventh Umbral Calamity by punching Dalamud out of the sky. In that timeline, the Seventh Shard still exists. In all other timelines, it doesn't. Likewise, in the Eighth Umbral Calamity timeline, the First no longer exists, while it still exists in our timeline.

The short story 'Tales from the Shadows: An Unpromised Tomorrow' seems to suggest that these individual timelines are completely disconnected from each other once the 'flag' event has passed. When Biggs III and his team transported G'raha back in time, the Crystal Tower disappeared from their skyline entirely. The implication being that they couldn't backtrack into our timeline. There is of course the question of what happened in the time between the Warrior of Light's death and G'raha's departure from the Eighth Umbral Calamity timeline. You still have the likes of Emet, Elidibus, Hermes, and Meteion floating around. But I think the main point of that story was to show that humanity would find a way forward on its own, even without the Warrior of Light's interventions.

'Though we shall remain forever on different pages of history ─ and different books, besides ─ I take comfort in knowing we strive for a future of the selfsame brightness.'

[Cleretic]

(and technically space since it cordoned off itself and the immediate space around it into a bubble of time).

Final Fantasy time magic has always been more of a 'space-time magic' thing anyway (I wish I could pinpoint an actual reason why, either culturally or in game design, but I never have). Even its first implementation in FFV gave it Gravity, Banish, Teleport, Comet and Meteor. And Silence, but I feel like that was just a 'we need to put it somewhere' thing.

Which I've always felt like was completely fair. Straight-up time magic is actually a pretty narrow space in the context of 'RPG spell kit', and lacks some particularly important elements, most crucially 'direct damage options'. Giving it space-focused spells is a pretty natural way to extend its niche.

[SentioftheHoukai]

The 8UC remains what it is, and it's not going to see the light if day even once more in all likelihood. It's part of Endwalker's dirty laundry, and is better off buried for the good of the narrative insofar as the devs are concerned.

As for time travel itself, I too believe they'll likely bury that hatchet post-Pandaemonium. It's a consistently convoluted plot point that they see no further need for at this time.

[Cassar]

In Tales from the Shadows there's a very nice story about what happens to the 8UC timeline immediately after the Crystal Tower is teleported, and it branches off the timeline. The ending could be seen as a cliffhanger and they might mention it again in the future, but maybe not.

As to how time travel works in this world, it's a little complicated, but I've spent months looking into official stories, re-watching cutscenes, watching QnAs with the devs and (the most helpful of all) asking around in this forum. Here's my conclusion:

The game uses both the alternate timeline method (Avengers Endgame), but also the unique timeline method (Back to the future). What defines when they use each might seem as a "mess" or as something completely arbitrary, but it actually makes sense. See, the timeline is only branched when the actions made in the past were detrimental enough to make it so that the original timeline couldn't possibly exist anymore. And so, instead of disappearing, the timeline simply branches off and allows for both possibilities.
And yes, there is a causal loop in the story, but that doesn't mean that the loop needs to be completed every time, because if it doesn't, the timeline would simply branch. So for example, in the 8UC timeline, the WoL never went to Elpis, and therefore the loop couldn't be completed, but that's fine, the timeline will simply branch off but will still share the same origin, because there's always going to be at least one timeline in which the WoL does go to Elpis and ensures the loop exists, and every other timeline can enjoy freedom from this obligation and do as they please! (At the cost of being branched off, of course)

[AwesomeJr44]

As for time travel itself, I too believe they'll likely bury that hatchet post-Pandaemonium. It's a consistently convoluted plot point that they see no further need for at this time.

I certainly hope they do. Time travel is a very difficult thing to write well, and Endwalker has proven that the writers can't use it properly.

[RyuDragnier]

I certainly hope they do. Time travel is a very difficult thing to write well, and Endwalker has proven that the writers can't use it properly.

Again, I think Radiant Historia was the only game I've seen do time travel well. I'd include Chrono Trigger, but well...you notice cracks in that one if you stare too hard.

[VigilanteXII]

And yes, there is a causal loop in the story, but that doesn't mean that the loop needs to be completed every time, because if it doesn't, the timeline would simply branch. So for example, in the 8UC timeline, the WoL never went to Elpis, and therefore the loop couldn't be completed, but that's fine, the timeline will simply branch off but will still share the same origin, because there's always going to be at least one timeline in which the WoL does go to Elpis and ensures the loop exists, and every other timeline can enjoy freedom from this obligation and do as they please! (At the cost of being branched off, of course)

I don’t think there was a causal loop involved. Believe Elidibus called it a “convergence of timelines”. The way I understood it, there’s basically two timelines, one where we went to Elpis and one where we didn’t. But since those timelines are almost identical, except for the memories of a few people, the timelines didn’t split, but kind of just collapsed into each other. That’s why Elidibus mentions that he both remembers us being there and us not being there, he has memories of both timelines, even though they conflict with each other.

It’s also why he’s very adamant that we don’t change anything, since doing so would cause a split and would most likely have left us stranded in that timeline (and would have left the original timeline short of one WoL). Admittedly we did a pretty bad job at that, but the memory wipe thing as well as Venat making sure to repeat history despite her new found knowledge made sure that our time there was ultimately of no consequence.

That is, until Pandemonium. Who knows where that is gonna lead.

[Iscah]

I don’t think there was a causal loop involved. Believe Elidibus called it a “convergence of timelines”.

I don't think Elidibus ever called it that, although Hydaelyn did - but then it could have simply been a poetic way of saying that the time loop is going to be completed soon.

It's worth noting that the description for the Argos mount highlights that we earned his trust prior to our first meeting with him on the moon "owing to the quirks of time travel", and of course Hydaelyn herself is also aware of those events already or she couldn't comment on it when we met her on the ship, indicating that we are already in the time-travel-affected timeline by the beginning of Endwalker.

So it cannot be that we change the timeline by travelling to Elpis. Those changes were already in place.

My own take on Elidibus's inconsistent memory is that it could be due to his fragmented memory being somewhat restored by receiving all of the Convocation's memory stones, which were partly produced by Emet and therefore just might contain his subconscious memory of meeting us in Elpis.

[Lyth]

I had a similar interpretation to Vigilante when I finished Endwalker.

When you first meet Hydaelyn on the boat ride to Sharlayan, she tells you the following:

'Even bereft of guidance, you and your companions have accepted the burden of this star's troubled past. A conjunction has begun to form; an intertwining of your time and mine.'

Again, just prior to your departure from Elpis, Venat uses the same words:

'You may find your world to be very different. Or perhaps the erasure of our friends' memories has sown the seeds of a conjunction between us.'

Both these lines seem to imply that the loop wasn't always there, but rather that certain conditions had to be first fulfilled in order for the conjunction to occur, such as G'raha preventing the Eighth Umbral Calamity, you putting Venat's clues together and travelling to Elpis, and then the Kairos memory wipe. I suspect that only because you fulfilled the prerequisites that some of the consequences of the loop (like Argos recognizing you, or Elidibus having memories of you on Elpis) started to manifest in our timeline. That's what is meant by 'forming a conjunction'.

Likewise, when you call out Venat's name in front of the Mothercrystal, only at that point does she realize that the loop has been successfully completed:

'I see... thou didst travel into Elpis.'

If the loop was always predestined to occur, then she would have just taken this as a given. So it was also possible that you might not have met the requirements for the conjunction to happen and you might have travelled to the Mothercrystal without travelling to Elpis.

[Absimiliard]

Venat is not an exception to the loop, merely a key participant thereof. It could repeat ten thousand times, and she would always be just as unsure if it had been completed successfully until the revelatory moment. We've seen nothing in-game or out to indicate Venat has any kind of special awareness that transcends that of other major players in that part of the story. If anything, her awareness seems a bit more limited on some levels.