Weltall

The intent of a Shard is related to how you access the magic. You're Initiated into Preservation's magic by the 'snapping' process in which you reach out to Preserve yourself (and every time you use ityou're Preserving your own strength by drawing power out from Preservation directly) while Ruin's magic is accessed by having the intent to steal power from (ie, to Ruin) someone else. You get access to Surgebinding by swearing to and following ideals (being Honorable) and Endowment's magic is literally a gift from the Shard to the native Nalthians, with the added benefit that every time anyone uses Awakening they're carrying out that Shard's intent. Burning metals in allomancy isn't Ruin-aligned any more than draining color in Awakening is Ruin-aligned or damaging gemstones while performing Soulcasting is Ruin-aligned.

Depending on what specific meanings you attach to Autonomy and Dominion, she might have approved of Odium going after the latter (and maybe even helped) or more broadly approve of what he's doing in general. She even says outright that she admires Rayse's initiative in Oathbringer. She may not necessarily be an ally of his but that doesn't mean they can't have occasionally aligning interests.

My guess is that once you extracted the iron from someone's blood and made a spike out of it, it would see itself as 'an iron spike' in the same way that a cake quickly begins to see itself as a cake rather than a collection of flour, sugar, eggs and so on. Consequently, it shouldn't have any special protection against hemalurgic decay. I think this would be related to how the Metallic Arts don't care about the source of the metal, just that it's the right kind. An iron spike forged from ore on Scadrial, one forged from Nalthian ore, one Soulcast from wood or one made from blood-extracted iron would all be the same as far as the magic is concerned.

Gold is an illustrative example here since one reason it's been historically valuable is that it doesn't rust or otherwise tarnish. This is because it doesn't react chemically with almost anything you can reasonably expose it to (like gaseous oxygen and nitrogen, water or common acids) and the circumstances under which you can oxidize it aren't ones that any human is going to reasonably be exposed to. Chromium is another highly nonreactive metal that happens to be part of the Metallic Arts. Atium and lerasium are probably at least that nonreactive. We know it's not a universal property of godmetals (harmonium is explicitly chemically reactive) and we know they're not immutable to non-magical means since you can melt atium and lerasium for alloying purposes but for the most part the godmetals are generally likely to be nonreactive to anything beyond extreme conditions.

It's also possible the ancient Radiants left that gate open on purpose. We know they wanted the city to be found eventually given the care they took to create and then hide the gem archive. Leaving one unlocked in a place that wasn't currently inhabited served as an easier way to hint to future generations where to find Urithiru, should knowledge of its exact location become lost, as it was. You still need a Radiant to open the way so it's not really much of a security risk and less of one than leaving an unlocked gate in a major city, but it still leaves a route open for people to find their way to the city when necessary.

Mraize is probably one of the people in the cosmere most likely to be able to survive on Patji long enough to grab an Aviar and return through the Perpendicularity before one of the many things on the island that can kill you (broadly defined as 'absolutely everything') gets to him. Given how much he loves talking about hunting and he's got a trophy collection, Patji is probably his idea of the best vacation spot in the cosmere.

I don't think Brandon gives away anything other than White Sand (Prose) and Aether of Night (and maybe Mistborn Prime?) other than those excerpts he puts up on his site.

It's a Skaze, the Dominion-leaning counterparts to the Seons. One is seen earlier in the story, when Hrathen and Wyrn communicate directly.

As mentioned, unless the Drominad System looks especially weird the Ones Above could simply maneuver out of the plane that the planets and the asteroid belt are on and thus never worry about running the latter. To quote that great source of astronomical knowledge, HHGTTG, space is big, really big. And comes in three dimensions.

No, the Investiture would cycle through the system and go back to the Shard eventually. What happened with Ruin and the atium was that Leras managed to split off a chunk of the former's power and set it to recycle constantly back into the Physical Realm, thus keeping it from Ruin's immediate access. Even if converting the liquid Investiture to godmetal form temporarily took it out of circulation (and there's no reason to believe an ordinary mortal could force that kind of thing upon a Shard if things weren't already set up to work that way) it would go back eventually in the same way that Ruin was able to theoretically reclaim his 'lost' Investiture once he was free.

We know for certain that they don't. Sazed mentions that he gained an impression of something called Adonalsium when he Ascended, which is a far cry from the actual knowledge that Ati and Leras would have had. The understanding he gained in Ascending came from the Spiritual Realm. Separately we know that a Vessel does not leave any imprint upon the Shard.

Shallan does think to herself (paraphrasing) that she had a weapon ten heartbeats away during Jasnah's 'ethics lesson' but we don't know if she could have actually summoned Pattern then and the heartbeats comment that we see reflected in WoR whenever she does summon him before the end make it clear there's a mental block there one way or another.

In Arcanum Unbounded she's able to discuss how Braize is a very cold planet even though she avoids actually visiting there for obvious reasons. This doesn't match with Kalak's recollections of the place as being hot; he mentions fire three times during the Prelude. It's possible that there's an inversion of temperature in the same way that we've seen a solid/liquid inversion on Roshar and Scadrial, so if Khriss goes to a place in the Cognitive Realm and it's bitterly cold she can deduce that it must be uncomfortably hot in the Physical. It's also possible (though this isn't mutually exclusive to the first idea) that she can observe the planet using a mix of Cognitive Realm snooping and looking at it from the Physical while on Sel and make the same sorts of observations that astronomers do today in order to figure out the physical characteristics of a world she can't visit directly.

Gloryspren explicitly react to the belief of the person they appear near that they've done something awesome, not that other people think so. This is both amusing and relevant Dalinar is doing something storming Awesome* at that point so it's not terribly surprising that he suddenly attracted a bunch of the things, in the same way that Kaladin attracts lots of windspren when he's being especially Windrunner-y. * This statement has been approved by Lift, who also tried to eat it.

I think a Sylpoongun might run into the upper limit on how big a spren can get, even before you get into the question of whether three separate bits with differing properties (gun, cable and spear) could work. And how you'd actually launch the last one and why you wouldn't just make her a javelin and throw her, or go with the common suggestion of a Shardchakram... But you made me crack up just thinking of that word, so bravo. xD

Speaking of RPGs, Brandon has admitted he's a big fan. He talked a bit at one point about playing D&D growing up and at another point he mulled over how you could make a feruchemist work as a prestige class. He's also a JRPG fan, especially of FFX which just might explain why Oathbringer's description sounds so much like Tidus' most iconic sword design. Really, all Knights Radiant are close to the Paladin ideal, mixing their magical weapon and armor with Surgebinding and being bound by a code of conduct which (between all the currently known Ideals) encompasses a lot of the typical Paladin restrictions, though not all Radiants will be bound in the same way so it's nothing like a 1:1 comparison. Which kind of goes with what's happened to the class in later editions that allow more flexibility. Skybreakers for example (at least as they're currently operating) have a good deal of resonance with 5e Paladins who follow the Oath of Vengeance. Windrunners are more Oath of the Ancients (putting 'good' before 'lawful' and so on. I'd agree that Brandon probably has some influences that he's drawing on, even if some of them are subconscious. For the specific powers of allomancy, he's outright confirmed they were developed from the standpoint of 'what skills would a team of thieves find useful' and then working out the details from there. That's probably more in line with the Monk class, though given that stories of warriors able to do the kinds of things we see in Dragonsteel Prime go back waaaaay before D&D, it's probably more a shared influence than something Brandon would have even unconsciously been drawing on. Separately Brandon's mentioned that you could fairly call Hoid a Bard. No comment on whether or not he is a Spoony one.

Also, Brandon has confirmed that Vasher has not been to any worlds we've not already seen him on: As an aside, he's mentioned that Khriss and other Silverlight scholars know of Vasher and consider the Five Scholars to be their spiritual predecessors but he hasn't confirmed if the two have ever met. Given that Khriss specifically tracked down Wax to get direct information on the mechanics of being a Crasher, I'd be shocked if she hasn't at least attempted to do so by now, given how much she could theoretically learn from him. And if Nazh were to go with her, he and Vasher could see who could out-grump who. Darn, now I want to see that happen...

Shashara was Nightblood's first wielder and presumably had plans for her potentially immortal life that didn't include getting murdered shortly after Twilight Falls. It's entirely possible she was purposefully vague because she never planned on letting it out of her hands, thus leaving her in the position of getting to say what counts as evil. Nightblood 'knows' that his user is equipped to judge good and evil. It's also possible of course that she didn't even try because evil is such a vague concept that it would be an extremely difficult thing to visualize in more concrete terms and that could cause problems in the Awakening process. Not that these are mutually exclusive ideas.

I kind of like the idea that Bavadin is/was a Dragon since we know that they're shapeshifters. When Brandon tells us not to get too hung up on "gender, race, or even human appearance" it might be that Bavadin's whole avatar scheme is just a superpowered extension of the kind of shapeshifting that she could already have done pre-Ascension. But that's just guesswork on my part.

FYI, everything in the Cosmere has a spiritweb (aka sDNA aka 'Spiritual template') which is fundamental to things like Forgery which can affect material that was never 'alive' in any way we'd recognize. Hemalurgy however requires blood in motion to work, which is why you can spike things into or out of animals but you can't use it on plants even though they have a spiritweb.

For Kelsier to be a mistborn, he absolutely needs to have a Connection to Preservation. That's literally what lerasium does when consumed by someone who isn't already a mistborn, makes that Connection. Ruin isn't involved at all; the 'cracks' in the spiritweb are a Cosmere-wide phenomenon and are especially obvious on Roshar. Since the power comes from Preservation, there really isn't room for Kelsier to be influenced by another non-Scadrian Shard. Plus, Secret History gives us Kelsier's recollection of his snapping. It was Leras' voice he heard, telling him to 'SURVIVE', a fact confirmed by Leras himself as literally the last thing he does before dying. There may be an unanswered question as to why Kelsier didn't snap earlier (it's entirely possible that Leras arranged things just so because his plan required Kelsier in order for everything to work at the end) but there isn't room for a third Shard to be meddling.

Skin grafts are definitely possible, it's mentioned several times that the most common use of Bestarin is to rapidly heal wounds by grafting a bit of animal skin onto the affected area and Taenen at one point takes a chest wound that Raeth thinks would have incapacitated a normal man for months and he was perfectly fine within an hour due to a graft. My guess is that you can't graft anything 'new' so you can't add wings or extra arms to a perfectly healthy individual, and even if you had a wound in a convenient location I'm not sure that your spiriweb could necessarily process a full arm attached to a minor shoulder wound or anything that's not reasonably close to whatever was there before. Of course, wings have a special problem which is that humans are not at all suited for flight and there simply aren't any wings on an existing Earth species that could lift a full-grown human. We can only guess at the Realmatics of Aethers, though there's an intriguing WoP that there's a reason that Brandon went to so much effort to keep the system in the Cosmere even once he trunked the original novel (ie, first trying to introduce them into The Liar of Partinel) so there's gotta be something interesting happening 'behind the scenes' with the magic. The way Ferrous works in particular seems like it would be really interesting so I hope that system remains in the rewrite, like we can assume Amberite will given that we've seen one of those Aethers already. As Bestarin healing Realmatics goes, my guess is that it functions on the standard Cosmere model so if the user took a wound that they couldn't magically heal and came to Cognitively accept that wound as part of them, they couldn't graft a replacement so long as they continued to perceive the wound that way. But given how Bestarin bonds are used to healing, I suspect they would rarely if ever get into that situation and they could graft a replacement limb, say, by just reopening the wound and giving the animal replacement somewhere to attach.

To add a bit to what @Calderis said on compunding, remember that almost anything a compounder can do can also be done by an ordinary feruchemist, assuming sufficient time is given to store a given trait. They just can't do it nearly as easily. See Wayne, who can perform amazing healing as long as he has enough stored health and Miles-level healing with the unkeyed goldmind. The obvious exception is that Rashek's trick to prolong his life required compounding to get around the zero-sum nature of ordinary age storage. And I agree that Divine Breath healing should work too. It healed Susebron even though he'd never known a time when he wasn't tongueless, so between that and his upbringing his Cognitive self-image probably included that and would have filtered any normal healing, but in this case it didn't and his tongue was healed. True, he needed that tongue to Awaken rather desperately but I'm not sure immediate need can override an ingrained image of self that easily.

Other worldhoppers can manipulate Connection without hemalurgy, like the Seventeenth Shard members in the Purelake interlude. Galladon in particular stands out since he's got Dula grammar slipping into his sentences, which is a sign of Connection-based translation used by someone who hasn't actually learned the local language(s) and we know there's a Scadrian in that group too, Demoux. Felt is likely using a similar if not identical method, though it's also possible he's actually learned Alethi outright and is speaking it normally. I don't remember offhand if he uses any odd expressions, just that Dalinar notes his short size and 'Shin' eyes as the obvious 'Not From Roshar!' indicators. Other obvious cases are Vasher and Vivenna, who are definitely using Connection-manipulation without local language skills, given how both say things that the magic is clearly struggling to interpret and so outputs literally, to the confusion of their audience. All that said, we know that Connection can be stolen hemalurgically as Brandon has mentioned that you need at least two spikes to steal magic from Sel, one for the magic itself and one for Connection to the right geographic region. But we have no clue what metal could steal this aside from the do-anything metal that is atium. Hemalurgy Table when? xD

Well, there are some limitations. You can store spike-granted powers in unsealed metalminds and allow anyone to use them (with whatever hacks may be required to work with non-native Investiture) and do crazy things with nicrosil compounding but the powers go with the spikes so when you take them out, they'd need the medallions to use any powers that aren't naturally part of their spiritweb. And there's limitations on the current understanding of the Southern Scadrians vis a vis how many powers you can use at once without the medallions interfering with one another. I imagine it would be even worse once you start mixing other Shards' Investiture. Atium is more efficient and due to its universal nature it makes for easier spiking but it's not required; with the right knowledge you could use other metals to steal things. Also, with Trellium seeming to be a universal metal as well, it's possible that all godmetals share this property.