The first retroactively-confirmed sightings were in the twenty-teens; their presence became indisputable when their major offensive began in 2038.

>and basically set human progress back a couple of thousand years by
>basically turning every human nation back into an island.

A couple of thousand years might be a bit of an exaggeration—it's not as if all the advanced technology on Earth stopped working—but it certainly did no economic or geopolitical good.

>Communication or transport between anywhere on Earth was stopped by
>them by force

Only by sea and air. Overland transport and hardwired communications were not affected, for the most part. The Fog did not appear to concern themselves much with what went on within the planet's landmasses, only between them, and the farther away from the coast you got, the less directly their influence was felt.

>until they abruptly got up and walked away as quickly
>as they came for no clear reason.

If anything, more quickly, in light of the retrospective realization that people had been spotting them at sea for upwards of 20 years before they attacked.

>All Fog ships are intelligent cores based around huge clumps of
>nanomachines, and are basically all characters from either Kantai
>Collection or Arpeggio of Blue Steel.

They didn't seem particularly intelligent at this time of this story, nor were they characters at that time in any meaningful sense. By the 25th century, that seems to be correct so far.

>In the case of the former,
>they're all antagonistic, but from what you've been hinting at the
>Abyssals were created by humans experimenting on them?

So far, the only character we've seen in UF whose appearance is based on an Abyssal is a ship that was built using a range of poorly understood alien technologies. If there are more of them out there, this would not necessarily be the origin story for all of them.

>Or they take
>the form of experimental ships which were never created?

There were a few Fog ships during the 21st-century war that were based on proposed-but-never-constructed designs from World War II.

>This is their
>first inning but now they're largely reappearing in the OOTR
>storyline.

Yes.

--G.
-><-
Benjamin D. Hutchins, Co-Founder, Editor-in-Chief, & Forum Mod
Eyrie Productions, Unlimited http://www.eyrie-productions.com/
zgryphon at that email service Google has
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