Regulators principles

[Vallavia]

Hi fellow players and lore fans !

I was asking myself a few questions about the principles behind the regulators and its actual effects.

We know their basic function is storing souls, and with the souls of the deceased they can live as long as they have souls stored in their central unit. We know too with the Arcadian they can store souls of monsters and beasts, and that's where I'm coming from:

it looks to me kinda the same thing as what happens between Ysayle and Shiva ?

Even if Ysayle needed some crystals in some cases to compensate the aether she did not have in sufficiently large quantities... (though if I remember correctly, after passing through the barrier of Azys Lla, she didn't have crystals to transform and destroy that empire airship, so not to say it's kind of a plothole, but crystals don't seem always needed aside from bringing the missing aether)

Though I'm still wondering why and how the body of the fighter in the Arcadian can adapt to such physical changes, even if the price to pay is great, it seems to be soul enhancement or "fusion" of souls like that of the reaper and its master. In the case of the reaper it seems more like the avatar or void creatures is trapped or called through the soul crystal...

The others in this thread have already addressed it, but you're operating on a completely different set of facts from what's presented in the game to manufacture evidence for a parallel that doesn't exist, and dismissing any textual evidence contrary to it as a 'plot hole' instead of, well, 'things that were plainly presented in the game'. This makes it difficult to understand your question as the premise isn't factual.

If I am understanding correctly, though, I would assert that the 'uncharted waters' of it all is very intentional on a narrative level, as is everything in Alexandria: we are in completely new territory and the kinds of soul-crafting and technology they're currently doing there are beyond the wildest imaginings of anyone on the Source before the Alexandrians arrived. This is kind of a major theme in the latter third of the Dawntrail MSQ; while it leaves a few open questions on the precise morality and necessity of it, it's also very clear that the narrative considers the sheer scale of the soul manipulation in Alexandria as an affront to nature, and the whole premise of Arcadion is that we're entering on a wager that we can end the practice in the arena. This is all to say that the mechanisms of this technology are completely novel by design.