DracostarA

@Quantus WoB has mentioned that surgebinding is a combination of Honor and Cultivation's Investiture, with both honorspren and cultivationspren being radiant spren, so I don't think there is necessarily a need for a pure Cultivation magic system. On the other hand though, I remember Rock using the Shardbow and since he's the only person to have used it onscreen without the assistance of Shardplate, there might be something more going on there. @Calderis I don't think the 9-centric quality Braize has is necessarily relevant here, since while there are 9 Unmade, the Voidbinding Chart shows 10 'orders' and Khriss mentions the '10 levels of Voidbinding' so Voidbinding and Surgebinding have 10 'surges' and 10 'orders'. The issue with Ashyn is what we know about it and its disease based magic (which, IMO, would fit the qualification of being a more esoteric set of abilities) but does not necessarily follow the 10-centric structure the other two have. All in all, I am of the opinion that there is a lot more to Voidbinding than what we've seen, and I think Venli's book should give us a much better idea of what exactly the Fused are doing, and what exactly Voidbinding is.

@Quantus My argument is just that so far we have (to my knowledge) not seen any character mention anything suggesting they understand Voidbinding - just references to it (Renarin, Fused etc aren't made explicit yet) while we have seen people like Navani and her colleagues understanding some complex Fabrial technology. While Fabrial knowledge is not significantly widespread, I'm just contending that with what we have seen it would be false to claim it is more esoteric than Voidbinding.

@Quantus But to be more esoteric means this third system just must not be nearly as well understood as the other two, and given how much knowledge there is in-world on Voidbinding (i.e. near to none from what we've seen so far) compared to Fabrials - where we've seen some fairly advanced fabrials made in the past and plans for others in the future - I don't think the claim can be made that Fabrial technology is more esoteric than Voidbinding.

@Quantus The suggestion Khriss makes of the third set of abilities being 'entirely different' to Old Magic and Void/Surgebinding does give credence to the idea of some sort of yet-unseen Fabrial technology. The Fabrials we've seen so far are either Surges or basic magitech so I think if they are the third type, it is definitely something vastly different to what we've seen. However, what we HAVE seen of Fabrials is, I'd argue, the opposite of esoteric, without much mystery and is treated as a science - I think if I'm wrong on the third set of abilities, it will likely be something new that comes up at the end of the first half of SA or during the second half (after all there'll still be surprises leading up to the end of the series so I'm sure there'll be a srpeading out of revelations. Of the options you put forward I think A, E and F are the most plausible. It has been mentioned that Braize is home to only Cognitive Shadows (I believe only the Heralds and the Fused are ever there) so I doubt it's there, and Ashyn's magic would have been named Surges by Rosharans so F is still a bit iffy for me.

Ignoring what Kelsier may or may not be like in Era 2 (I don't think we've seen enough of him to make an accurate judgement), taking advantage of a conflict to increase power and influence seems pretty much right in Era 1 Kelsier's wheelhouse, so I don't think it's too far fetched for him to be the leader. I myself am not sure he will be, but of all the characters we have seen Kelsier is the one best suited to forming a behind-the-scenes worldhopping society with a Southern Scadrian in it. But there is no reason the Ghostblood leader could not be an entirely new character, so I'm very on the fence here.

@Juanaton I agree that WoB trumps Khriss, but then I wonder what is the storytelling purpose of including that? I just don't think it makes sense for Brandon to suggest a third set of abilities and for them to not exist. What purpose does it serve for the reader to think there may be one more set of abilities besides Voidbinding and Surgebinding when in truth there is none such ability?

@dvoraen I believe it's mentioned in Edgedancer that the 'black dust' is left behind by Wyndle as he moves.

@Calderis Sorry I'm not sure if I am getting my point across well. I agree fabrials are a magic system and am not disputing that. What I am saying is I believe the 'more esoteric' set of abilities is but a combination of Surgebinding and Voidbinding, and not that it is another magic system in and of itself.

@Leyrann No, so I mean to say both of them are true : Fabrials are a type of magic but I wouldn't consider them a set of abilities. So my argument is that Renarin is using this set of abilities which uses both Voidbinding and Surgebinding, and so is not a distinct type of magic but forms a new set of abilities that regular Surgebinders and Voidbinders would not have.

@Juanaton So you postulate a third system of voidsurging or something along those lines? @Leyrann The thing that makes me believe Fabrials are not what Khriss was referring to with this are twofold: In the same Ars Arcanum she mentions and discusses the basics of Fabrial technology, so if she thought it was related she probably would have mentioned it alongside Surgebinding and Voidbinding. She specifically mentions 'a set of abilities that is even more esoteric than the Voidbindings' which, in my opinion, discounts Fabrials since they are a magical technology accessible by anyone and not abilities. If Surgebinding and Voidbinding are the only other forms of magic on Roshar, I'm not sure where a whole new set of abilities would fit unless they are a combination of the two, which Renarin appears to have ('Surgebinding' Progression and maybe 'Voidbinding' Illumination? Though the future visions he have may be a combination of Illumination and Progression, though that's a discussion for another topic perhaps).

In Khriss' essay on the Rosharan system, she suggests that in addition to Surgebinding and Voidbinding, she predicts a third, more esoteric type of magic (and believes it unlikely to be the Old Magic). Could this perhaps be what Renarin is doing? He obviously is not a true Surgebinder, but neither is he a user of voidlight. While this does just seem to be a mix of the two, Brandon has always mentioned Surgebinding, Voidbinding and Fabrials as the only magic on Roshar. Obviously this may be a misdirection, but if not, I believe Renarin and the children of Sja-Anat to be responsible for this third type of binding. Also, Surgebinding is a blend of Honor and Cultivation, but is there confirmation Voidbinding is purely of Odium, or could it be a blend of Odium and Honor's Investiture?

That's not necessarily true. Since we don't know just how far apart the planets are in the Physical Realm, and in the Cognitive Realm, 'dead space' (uninhabited planets included) takes up almost no space. Therefore, like on the Shadesmar map, Roshar and Scadrial are adjacent in the Cognitive Realm. Maybe its faster however to get to Sel or Nalthis through FTL, since you don't have to pass through Shadesmar. Perhaps that is another reason - some places are easier by Cognitive Realm travel while others are easier to reach with FTL. Oh and since I forgot to mention, FTL is by far the safest way to reach Sel with the knowledge we have at the moment - that may be an incentive.

@Quantus @Calderis I agree the Metallic Arts at their most sophisticated may make it significantly easier to achieve FTL travel. However, I propose that like in BoM, necessity is the mother of invention, and if as old as The Final Empire Scadrians were Worldhopping (the method behind which I expect to have become public knowledge by late Era 3 or Era 4), what need is there to attempt to develop FTL travel. Much like Harmony's influence retarded the technological advancement of Elendel, I think unless there is some increased difficulty/change in Worldhopping ease there will be no drive to aim for FTL travel at all. One thing I am willing to consider is maybe FTL is easier for mass transport or for regular people without any Allomancy or Feruchemy than travelling through the Cognitive Realm?

Brandon has repeatedly mentioned that Mistborn Era 4 will involve faster-than-light space travel. Now, we know that to get to other shardworlds, the cognitive realm is a far easier way to get around, and we know some Scadrians have access to this knowledge. This begs the question, why the need for FTL travel at all then? I have a few possible ideas: There is a metal shortage: It makes sense in the future of an allomantic world that there can be a supply issue, so perhaps the motivation is to go to uninhabited planets to mine for resources. They want to go to non-shardworlds: Worlds without a perpendicularity cannot be easily accessed, so FTL may be needed to get to these otherwise inaccessible planets - but why would they want to? There is no longer a perpendicularity on Scadrial: Depending on conflict between Shards and movement between worlds Scadrial may no longer be a Shardworld in the far future. Though Harmony's Perpendicularity is currently unknown to us, Khriss and Nazh are present in Era 2 so there is some movement still. (This is the one I find the least likely) There is an issue with the Cognitive Realm in Scadrial: Much like in Sel, there may be events which make the Cognitive Realm hostile to large groups of people, which may link in with the Discord theory going around. Thus, FTL travel is the fastest way to get people offworld when necessary. Perhaps the most simple reason: They just do it because they want to explore. Scadrians might just want to explore unrestricted to populated worlds and Shardworlds and want to explore the Cosmere to the fullest. If anyone has any ideas please bring them up. I'm not sure if I'm reading into this too much but I think there must be something slightly more going on since we know FTL isn't required for interplanetary travel.

Agreed, we are still widely speculating, but also the Lifebrother fits the convention held by Stormfather and Nightwatcher as well, which I feel lends some potential credence to the idea.

With the non-binary idea looking promising, I am a fan of the 'male' aspect of the Sibling being the Lifebrother mentioned by Szeth (with an unknown female counterpart, potentially Deathsister but that seems too obvious). The only real support there is for this theory is that Szeth refers to Heralds by name, so it is unlikely to be a Herald's title, and obviously that a 'brother' is a 'sibling' too.

If the Sibling is the Spren of Stone, which I think is plausible, perhaps it could link to the Horneater Peaks mythology. The three 'Gods' mentioned may be the Godspren: God of Forests : Nightwatcher God of Waters : Stormfather (tentative, since this god was responsible for the lakes on the Peaks, which Stormfather could have achieved through rain) God of Mountains : Sibling, if responsible for the Stone. *Sidenote: Perhaps the Sibling could be the Spren of Roshar itself, a spren of Adonalsium altered by the presence of Honor/Cultivation?

From TWoK epigraphs. It may have been to far to mention 'by Radiants', but clearly it was built at one point, and since it mentions Alethela, I believe that means this is after mankind became dominant on Roshar. So if Urithiru was built, clearly it was designed to be powered by a powerful spren, but what were the spren's capabilities before its building is what I wonder?

I think a popular theory is that the Sibling was the spren used to power Urithiru and make it function as a city. However, we also know that Urithiru was built and designed by Radiants, so before its construction the Sibling Bondsmith would still have existed, just not have been required to power the city. We know the Stormfather and Nightwatcher have a range of abilities on their own, as well as their purpose on Roshar. What else do you think the Sibling was capable of before its use as Urithiru's spren?

Brandon mentioned that First from the Sun was referenced in the Oathbringer letters I believe, so I think it's pretty much confirmed that Obrodai is First from the Sun.

I believe it's confirmed to be Eshonai.

So I came across this thread on Reddit and thought it could be a plausible theory for the identity of the Sibling. https://www.reddit.com/r/Cosmere/comments/7occ6b/sa_stormfather_nightwatcher_and/ TL;DR: At the end of WoK where Taravangian reveals himself to be Szeth's master, he wonders if the 'Lifebrother' sent Szeth to him. In the context it seems to be some Shin mythology, but the 'brother' links to the 'Sibling' idea and 'Lifebrother' fits the same scheme as 'Nightwatcher' and 'Stormfather', and may be the name of the Sibling (since people seem to think it can also bring Urithiru 'to life' in a sense, this would fit also). Thoughts?

I agree, Autonomy does seem to want to maintain its influence where it's spread. I think another reason for this could be [Spoilers for Shadows for Silence and Arcanum Unbounded]

Through a lot of recent WoB and the second letter in Oathbringer, it's almost confirmed that the aviar are a product of Autonomy investing in Patji. I've noticed that on the two worlds we know of invested by Autonomy, the investiture that we have seen does not lie within people, like in most worlds, but instead are in unintelligent beings, and are manipulated by people. 1. The invested microbes in the sand are what allows Sand Mastery to occur. 2. The invested worms on Patji are what gives the aviar their strange abilities. Perhaps this is a common theme for all places invested by Autonomy in the cosmere, or some pattern at least?

We know that Urithiru was intentionally made and positioned. Perhaps the Sibling has some other purpose outside powering Urithiru? Or perhaps it was created alongside the city.