Something doesn't add up regarding the connection between Amdapor and Norvrandt...

[ObsidianFire]

Diabolos' history in the Source is well documented. He's a high-ranking Voidsent summoned by Mach to unleash on Amdapoor near the end of the 5th Astral Era. The Amdapoori succeeded in sealing him up until you breach his wards at which point he leaves Amdapoor. The same thing goes for Feridad, the last boss of Amdappor Keep (Hard). Later, they would both turn up in Dun Scaith. Feridad would finally be defeated there and Diabolos would absorb Scath's power and be defeated.

However, since both of them are Voidsent, neither of them are really dead. They (and all the other Voidsent we fight) are really just possessing the bodies of whatever the mage who summoned them provided them with. Both Diabolos and Feridad are still alive in the Void waiting for some mage to summon them to the Source again so they can feast on aether.

Voidsent's forms (especially in the Source) are not their real forms at all and shouldn't be considered to be what the Voidsent really look like. Voidsent tend to like possessing specific kinds of objects and corpses... everything from suits of armor to eyeballs to gargoyles to people. As far as I know, we have never seen a person "transform" into a Voidsent because they were in an area that had "too much" Darkness. What usually happens is that a Voidsent kills a person and that body is immediately possessed by another Voidsent from the Void. You see this a lot in Haukke Manor (both normal and Hard). If anything, the closest we have seen to someone "transforming" into a Voidsent would be Nero in the World of Darkness raid. But even that doesn't literally make him into a Voidsent then and their. It instead infects his aether and he starts crystallizing in the Void.

Closer to the issue the OP brings up, there's like... three different proposed "causes" of the Flood of Light on the Source depending on which quest line you are talking about. The MSQ attributes the Flood of Light to Ardbert killing Mitron. The Role Quests attribute the Flood of Light to Ardbert getting his Crystal of Light. The 8-man Raid attributes both the Flood of Light and the origin of the Sin Eaters to Eden. So at this point... I think we actually need more info on what really did cause the Flood of Light. Because if it is Eden and Eden is what makes beings into Sin Eaters... How do we get Sin Eaters existing before Eden started turning other beings into Sin Eaters?

[YianKutku]

(Can time flow slower on the first? I don't remember if that was confirmed.)

Time can indeed flow slower on the First compared to the Source, as the Crystal Exarch explained. Sometimes the Source is faster, sometimes the First is faster.

However, assuming time only flows forward at whatever pace (even if it's effectively a time stop), the Amdapoori "seeing" a Sin Eater Forgiven Cruelty still requires some sort of future sight. Which can happen (see the list of prophecies extant in the FFXIV setting, eg Mezaya Thousand-Eyes and the Gerun Oracles), but it does seem kind of lazy narratively. ("It's magic, we don't have to explain it.")

Basically, the first appearance of Sin Eaters on the First, as seen by the denizens of the First, was about a hundred First years ago, after the Flood of Light's advance was stopped by Minfilia. The Flood of Light itself happened only slightly before that time, since Ardbert and co's adventures were also said to be about a hundred First years ago.

So the Shadowkeeper was "vanquished" (putting it as non-spoilery as possible) about a hundred First years ago, the Flood of Light happens, and Ardbert's crew sacrificed themselves to jump to the Source, where the 3.x patch MSQ happens. Minfilia joins Ardbert's crew on the return trip, returns to the First, where it is implied that not that much time has passed since the beginning of the Flood of Light. Minfilia stops the Flood of Light, Ardbert's crew minus Ardbert himself sacrifice their souls to help, and then Sin Eaters appear.

So the Sin Eaters would only have appeared after Minfilia went to the First, if judging by Source time. Which is obviously much later than the Fifth Astral Era time of Amdapor and Mhach and Nym, again going by Source time.

Therefore, the possibilities that allow Amdapor to see a Forgiven Cruelty Sin Eater would be as follows:

- Future Sight, as mentioned.

- Sin Eaters somehow existed on the First when the Flood of Light began, but declined to show themselves to the general populace for some reason. And at that time, the passage of time on the First was effectively a time stop while thousands of years passed on the Source. (This contradicts out-of-game lore interviews given prior to Shadowbringers, ie that a "proper" Flood of Light is just blank nothingness, but those could always have been retconned.)

- Time can flow backwards relative to Source and Shard.

[Atamis]

Therefore, the possibilities that allow Amdapor to see a Forgiven Cruelty Sin Eater would be as follows:

- Future Sight, as mentioned.

- Sin Eaters somehow existed on the First when the Flood of Light began, but declined to show themselves to the general populace for some reason. And at that time, the passage of time on the First was effectively a time stop while thousands of years passed on the Source. (This contradicts out-of-game lore interviews given prior to Shadowbringers, ie that a "proper" Flood of Light is just blank nothingness, but those could always have been retconned.)

- Time can flow backwards relative to Source and Shard.

I'll just repeat my previous post in tldr fashion since it seems it was ignored.
Sin Eaters can be a natural consequence of absorbing too much light aether. They were not necessarily invented on the first, but they are the first to suffer such on a cataclysmic scale. I would also argue voidsent are in the same position but being devoid of any aether well beyond simply draining the body of aethers.

So a completely valid explanation is Amdapor seen random sin eaters, maybe not from the first, maybe just in magic hammer space, and they copied it. I would assume getting something to become completely aspected to one aether is particularly hard, especially given cross contamination is possible. Maybe they didn't have the means to infuse something with pure light aether and instead chose to imbue a preformed block and statues with light aether to mimic it as best as they could.

I say sin eaters are a natural thing as the little boy in Amh Araeng in the Inn at Journey's End is slowly turning into a sin eater, it was not a forceful encounter. His aether was locked so only light could enter and everything else slowly seeps away or is being converted. Once anyone passes a thresh hold they are transformed into a sin eater. Normal people just wandering about don't chance because they can still regulate their aethers normally.

[ObsidianFire]

Sin Eaters can be a natural consequence of absorbing too much light aether. They were not necessarily invented on the first, but they are the first to suffer such on a cataclysmic scale. I would also argue voidsent are in the same position but being devoid of any aether well beyond simply draining the body of aethers.

Where in-game is this info from? We know what Voidsent are and they don't just crop up where-ever Darkness is strong. They are specifically summoned from the Shard that was Flooded with Darkness. And Voidsent were corrupted by the Darkness and are really just the corrupted life from the 13th Shard. Any time we see someone "turning" into a Voidsent in-game, a Voidsent from the Void is possessing their corpse. Sometimes the person's soul is still in there, most of the time it isn't.

So a completely valid explanation is Amdapor seen random sin eaters, maybe not from the first, maybe just in magic hammer space, and they copied it. I would assume getting something to become completely aspected to one aether is particularly hard, especially given cross contamination is possible. Maybe they didn't have the means to infuse something with pure light aether and instead chose to imbue a preformed block and statues with light aether to mimic it as best as they could.

Like it or not, the Eden Raid calls Eden the First Sin Eater and says it's the origin of all the Sin Eaters. This is a bit of a problem when you have what looks like things that originated from Eden existing before Eden ever sent the Flood of Light off.

I say sin eaters are a natural thing as the little boy in Amh Araeng in the Inn at Journey's End is slowly turning into a sin eater, it was not a forceful encounter. His aether was locked so only light could enter and everything else slowly seeps away or is being converted. Once anyone passes a thresh hold they are transformed into a sin eater. Normal people just wandering about don't chance because they can still regulate their aethers normally.

Sin Eaters are no more a natural thing then Voidsent are. Everyone in the 1st Shard will turn into a Sin Eater due to the Flood of Light infecting all of them with "seeds" of light which is exactly how Voidsent were created in the 13th Shard when it Flooded with Darkness. Being transformed into a Sin Eater doesn't speed up unless a person get really close to one of the high rank sin ethers though. Tesleen's transformation is show as being rather typical of how Voidsent "speed up" Sin Eater creation if Holmister Switch is anything to go by.

Allag did create artificial Voidsent... by cloning real Voidsent they summoned from the Void. They never actually "made" new original concept Voidsent. If Amdapoor were to be doing something similar, they would have to get a Sin Eater from a non-existant Flooded World of Light and then somehow copy that. The Source has never been so elementally tipped towards Astral or Umbral as the Void or the 1st Shard have gotten. So I highly doubt finding such a strong influence of Dark or Light on the Source would be possible.

I'm just saying... when the only source of a phenomena is someone Flooding a Shard with Light or Dark... none of that is how a world "normally" works. And in-game citations for a lot of these sin eater claim would be appreciated.

[TankHunter678]

I'm just saying... when the only source of a phenomena is someone Flooding a Shard with Light or Dark... none of that is how a world "normally" works. And in-game citations for a lot of these sin eater claim would be appreciated.

The raid storyline makes it clear that if they stayed in the Empty for too long they would turn into Sin Eaters. The Empty was created by Eden passing through and passively performing its function of transitioning all aether in its vicinity to extreme astral polarity. Minfilia stopped the Flood by asserting control over it with the help of the First WoL souls and putting it to sleep.

Given that Ardbert says that their world had always been tipped toward light then it makes sense that it was so due to the presence of Eden. Though by the way things look is that while Eden is slumbering it takes a lot to get it to wake up and start performing its functions. Which means it could have been passively sleeping for a long time, ever since the Sundering, but even while it is sleeping it is still performing its passive functions. Which means that any entity that wandered near it would see itself become a sin eater as its elemental balance gets disrupted and goes all towards astral. Which is how people get converted into Sin Eaters, by all of the elements that make up their body going astral. This is why victims hit with "light seeds" turn into Sin Eaters, because thanks to a cluster of light sending their entire elemental balance towards astral their body struggles to stabilize its elemental balance, so long as they kept receiving light aether the body would eventually be overwhelmed.

[geekgirl101]

Sin Eaters somehow existed on the First when the Flood of Light began, but declined to show themselves to the general populace for some reason. And at that time, the passage of time on the First was effectively a time stop while thousands of years passed on the Source. (This contradicts out-of-game lore interviews given prior to Shadowbringers, ie that a "proper" Flood of Light is just blank nothingness, but those could always have been retconned.)

Since sin eaters remain present where there is a strong Light source being emitted from a Lightwarden then there must be a point somewhere where there's a strong primordial Light presence for them to congregate, like a Bermuda Triangle where Light is at its strongest, and are unable to move beyond that point unless Light becomes more dominant on the rest of the star. This could explain why they weren't seen before by the inhabitants on the First. Emet-Selch summoned one to alter Vauthry before he was born so they must already exist somewhere. Like some have stated it's probably then a natural occurrence where overwhelming primordial Light aether warps living beings into Lightwardens and sin eaters. I think Thancred said something along those lines too when he ventured into the empty that if we remained in it for too long then the overwhelming Light aether would eventually turn us into a sin eater.

[TankHunter678]

Since sin eaters remain present where there is a strong Light source being emitted from a Lightwarden then there must be a point somewhere where there's a strong primordial Light presence for them to congregate, like a Bermuda Triangle where Light is at its strongest, and are unable to move beyond that point unless Light becomes more dominant on the rest of the star. This could explain why they weren't seen before by the inhabitants on the First. Emet-Selch summoned one to alter Vauthry before he was born so they must already exist somewhere. Like some have stated it's probably then a natural occurrence where overwhelming primordial Light aether warps living beings into Lightwardens and sin eaters. I think Thancred said something along those lines too when he ventured into the empty that if we remained in it for too long then the overwhelming Light aether would eventually turn us into a sin eater.

And given that Eden, a massive source of primordial Light, had been sleeping on the First then Sin Eaters would be able to form in its immediate vicinity, but until the light grew strong enough to reach across the world then the Sin Eaters would not be able to leave the isolated location that Eden was sleeping in.

[Ouen]

... at any point in time an Ascian could have setup a vision for one of the Amdapori to let them peer through the barrier and see these Sin Eaters. The goal obviously being to give the Amdapori a means to take the fight to Mhachi and their voidsent. With open war being possible it sets the stage for the War of the Mages and the calamity it sparked to follow.

I considered that Ascians might have had a hand in the matter, but it's hard to draw further conclusions until we know precisely what capabilities Amdapor had so I didn't explore that idea very much. However, reading your reply, a question that now occurred to me is why would they use Sin Eaters in particular? How would this empower Amdapor and facilitate more chaos than if the Ascians had not intervened? What did Amdapor and the Ascians stand to gain from this transaction that they would not have otherwise?

What benefits does simply shaping the golems into the aesthetic form of a Sin Eater confer? Wouldn't normal stone golems (e.g., the Clay Effigies, Mana Idols, and Mana Pots encountered while descending into the Crystallum) suffice? They already had normal golems that were very capable of fighting, why would they need to create additional golems that were doubtless more difficult to make than Idols or Clay Beasts?

A possibility might be that much like the patterns that arcanists and geomancers utilize or the way that various weapons have divots and carvings, certain patterns enhance the flow of aether. Taking the form of Sin Eaters might allow for stronger golems. However, I find this a weak justification for all the effort it would take for the ascians to step in and teach the Amdapori about cross-dimensional beings just to make their golems, already functional, more effective.

On a side note, something curious to me is that none of the "Gargoyle" statues in Amdapor Keep are identical to the gargoyle-type Sin Eaters (Tesleen's model). In fact, they are actually quite different if you examine them. Here's an album I put together comparing some of them.

If those were indeed made in the image of the Sin Eaters, then they're not 1:1 like the Winged Lion or Kuribu recreations. They are golems, but interestingly they are identical to voidsent, and NOT to Sin Eaters. This may be an oversight, as they probably didn't have models of the First gargoyle things made yet.

Also, this probably has no significance, but I found it interesting that the zombified Amdapori White Mages you fight are named "Amdapori Gargoyles" while the adds that look like what we think of as gargoyles are called "Putto."

[geekgirl101]

On a side note, something curious to me is that none of the "Gargoyle" statues in Amdapor Keep are identical to the gargoyle-type Sin Eaters (Tesleen's model). In fact, they are actually quite different if you examine them. Here's an album I put together comparing some of them.

Tesleen's transformation was different from the other sin eaters, that may have been down to her being instantly transformed by a more powerful sin eater rather than the lesser ones that take days to slowly transform.