
Originally Posted by
Eltdown
My current theory is the "Winterers" are an organization of individuals forced to "winter" in the Source for various reasons, who ultimately want to go home. Some might be from reflections that have been rejoined and somehow managed to escape the fate of their worlds. In the case of the Ninth, the rest of the reflection may now be uninhabitable, overwhelmed by lightning aether.
I'm more inclined to believe that...
"Winterers" is the name they finally came up with to denote the "sundered" Ascians from the Paragon unsundered three. It's worth remembering that until the Dimensional Fusion kicking off Dawntrail's second act Calyx was (presumably) stuck on the Ninth, given he's a data-based projection stored in the Meso Terminal until 7.3's denouement. The term "winterer" here, I think, is more intended to convey "someone who migrates," as their primary purpose seems to have been visiting other reflections to kickstart Rejoinings through long plays. This is what happened in the First (Loghrif and Mitron, until Ardbert & co. threw a wrench into things) and the Thirteenth (Igeyorhm). I'm not going to say decisively, but trends are trends...

Originally Posted by
mallleable
Food for my brain worms
Why is the portal opening process so violent? I think there is still the possibility that The Key could have been intended as a weapon, and not a simple tool. How were the Millala able to open their portal safely (unless they didn't)? Auracite is said to grant miracles for those with well intentions. Azem's symbol appearing on it is still a mystery.
I'm inclined to believe that...
Considering the "key" is the crystal in the chalice, and not the chalice itself, the explosion was an unfortunate accident that resulted from a test. The chalice appears to be an effort not to just use the Key at will, but control which reflection (or the Source) they land on. The Milalla (neé Lalafell) probably did not know what they were doing with the Key during the Calamity of Ice; they just used it to summon a portal that would take them somewhere more hospitable, with no care to how it worked or concern for where exactly they were going. But if you could control it and expand the effects...
The only thing I can say about Azem's symbol showing up in resonance when we fought the Queen Eternal is that it tells us the Key is somehow connected to the Ancients / Ascians.