Nitpicking

I am vaguely remembering WoBs, and I do not have time tonight to trawl the Arcanum, so ... I yield the field.

To me, the interesting question is, what happens when they die? Do they go to Braize, or just Beyond? If Braize, do they Return, or does Retribution have his servants torment them as the Heralds were tormented?

"Surges" were basically anything, before Ishar talked Tanavast into limiting them. Ashyn was destroyed by nuclear reactions caused by Investiture--microkinesis.

Ashyn was a apparently destroyed by microkinesis. The unrestrained Surges are enormously more than what Radiants are permitted to do.

The original question has to mean pre-Retribution, because Cultivation leaves Roshar when Retribution is created. The Nightwatcher still presumably exists, though.

Spoiler for Dragonsteel Prime. We see dawnshards in W&T and Sunlit Man. No metals involved.

When did Ishar summon Honor's Perpendicularity? It moved with the Stormfather. How do you think the Highstorm charged gemstones? You need a Connection to the Spiritual Realm to do that.

Tress wasn't as serious a story as this, so out-of-place words didn't seem as weird. At least, that's how I see it.

We know Honor's perpendicularity moved (back when it existed). Dalinar was opening Honor's perpendicularity. It never had a single location, normally it traveled with the Stormfather.

I have the Curse of the Philosopher Mom, so I have to ask, "Which feruchemical power? Which allomantic power? Useful for what?" Both metals are really cheap, so I'm not sure why you mention money drain. One advantage of being an allomancer: you're immune to heavy metal poisoning, apparently. I'd love to have, say, zinc or bronze or steel feruchemy, though.

BTW, I assume everyone knows why Brandon has precogs interfere with each other? [he asked mysteriously]

Lanceryn are not greatshells, are they?

So, the opposite of what Ishar did to spren? I think you'd need enough spren to open a Perpendicularity. Which means, as powerful as the Sibling (in aggregate).

By definition, infrared is beyond the visible spectrum. Specifically, the light waves are longer than any visible light, as opposed to ultraviolet light, where the waves are shorter than visible. To visualize atoms you'd need immensely powerful gamma rays (much shorter than UV), but in fact we use electrons or non-radiation methods like the scanning tunneling microscope. Gamma rays that powerful spontaneously generate particle/antiparticle pairs and lose a lot of energy.

Hoid is a Dawnshard, possibly. Four of those killed Adonalsium.

Kelsier.

Spoilers for Dragonsteel Prime and Isles of the Emberdark:

So ... at the end of Wind and Truth, Kaladin is both a Fifth Oath Windrunner and also replaces Jezrien as the Herald with Windrunner abilities. Will this affect his abilities? You wouldn't get a resonance, would you, since those are combinations of different Invested Arts/Surges/Metallic Arts/etc. We see Nale (who is also both Herald and Fifth Oath of the Skybreakers) and he doesn't visibly show any abilities that he would need two powersets to have. But surely it should have some effect?

Shai was able to turn herself into an Elantrian using a Soulstamp and a lot of unkeyed Dor. Elantrians canonically are more Invested than basically anyone short of major Splinters or millennia-old Cognitive Shadows like Yumi (or presumably someone like Hoid who is/was a Dawnshard). If you can become an Elantrian, I'd think becoming Returned would be easy.

Is it worth mentioning that Matin also has a nearly-Threnodite name? Matin is a Latin word for the hour of dawn. In Catholicism, it's a specific time at which certain services are held, IIRC.

So this is the list of categories at Brandon's site: Right-hand side of this page: https://faq.brandonsanderson.com/article-categories/contact/ Dust, dusk, what's the difference? (I reported it, so it might be fixed soon. It would be easy to fix.)

This seems to be a difference between spren and Cognitive Shadows: to the best of my recollection, we've never seen a Shadow turn into a metal.

Brandon made it very clear that Creation requires both Ruin and Preservation. If only Sazed had chosen that aspect when he took up both Shards. (Of course, presumably he would then have needed help from Virtuosity, Shard of artistic excellence. I wonder if Virtuosity was Splintered at the time of the Catacendre.)

If Cosmere axions work like our-universe atoms and molecules, you would have a hard time moving the oxygen molecules through the water while pushing the water away at the same time, since it would happen on a molecular basis, but fabrials are Cognitive devices (powered by Cognitive entities, spren) and would work on water as a whole, not on water and its constituents separately. In my opinion.

The Coppermind has a lot to say about the names of the Unmade. Mostly, they seem to be Semitic gods (e. g. Moelach = Moloch). Note that "ba" is an Egyptian term for one of the multiple souls a human being has, and "ado" could be the same root as in Ado-nalsium.