Xanpheon

The concept of Spren as a whole is quite interesting. Obviously they're splinters, but to what extent are "splinters" and "spren" interchangeable? WE know that the morphological differences between each "type" of sentient spren is largely down to what proportion of Cultivation and Honor make up each of them, but what about the emotionspren, or other lesser spren? We know they already existed before any of hte Shards arrived on Roshar, they were part of what prompted the creation of the sentient spren by the two Shards. They're obviously Spren too, but are they associated with any shardic intent? Or are they, instead, perhaps proof of splinters existing independent of Shardic Intent?

The Wind wanted to protect "all spren" from being absorbed by Odium. This seems to include emotionspren and Cultivationspren, even after the fusion into Retribution he shouldn't have had any control over their constituent investiture as they likely weren't created by Honor.

9 hours ago, DoctaDajman said:

I dont know what duralumin would do for a shardblade cut because we dont know what that metal would do... 

Definately if anyone wanted to be a shardblade killing machine I think an aluminum Gnat takes the cake. 

Not convinced about this, to be honest. Sure, there's an element of that, but the Shardblade can exist without needing investiture to "fuel" it. Deadeye shardblades exist without any stormlight to fuel them - they only "bond" when gems are placed in them, sure, but they can still exist without it. An aluminium gnat would burn out the investiture reserves but I'm not convinced they would stop the shardblade existing in it's already sharp state, even if it loses the soul-burning properties.

On 2/3/2026 at 3:02 AM, Trusk'our said:

It's been a long standing theory of mine that Hemalurgy (specifically the type that uses metals as a focus to rip off pieces of Spiritweb and then suture them onto another. Crystal/Cosmere-wide concepts of Hemalurgy may be different) actually scrubs much if not all of the previous Shardic association the stolen Investiture had, then aligning it with Ruin's Intent and instilling anyone who bears that spike with a Connection and Investment from Ruin. Similar to how other mangled forms of Investiture turn black and have a Ruinous vibe (such as Nightmares, Nightblood, and possibly the Midnight essence- though that last one is even further removed and might actually just be coincidence).

While I do understand where you're coming from with this particular stance, I'm not sure I agree.

Hemalurgy is ripping away a piece of a spiritweb and stapling it to another entity. Strength, speed, or the spiritual DNA to create a bond to Preservation, allowing the wielder to use an Allomantic power, for example. But using Allomancy as an example for this kind of works against the idea - in the books, advanced Seekers can sense the difference between the "tones" (pulses, but I'm using tones to tie in to the "source" of the investiture) - enough to tell what sort of Allomancy is being used. And Inquisitors don't have a different sensation to their power than anyone else when they use Allomancy - which indicates they still use metal as a key to Preservation's power to allow them to use Allomantic abilities.

Similarly, hemalurgy can't strip all identity from investiture as we know that it can allow a spiked Feruchemist to access metalminds made by the person who had their powers stolen from. It tracks the identity of the user - and thus likely also tracks the original "source" of the investiture.

I won't argue that it infects their spiritweb with part of Ruin's Investiture and gives whoever the bearer of the shard is a bond to them - we know it does - But I don't think it erases previous shardic affiliations.

Maybe, but unlikely.

Shardplate and Shardblade aren't an invested art, they're closer to mechanical uses of investiture - if the wielder is not a Radiant and thus the Shardbearer is just using deadeyes (or unoathed), then the wielder doesn't really use the investiture, per se. Resonances come from the natural interference of two separate Invested Arts/methods of manipulating investiture interacting with each other:

Quote

Questioner

I was wondering, with resonance. Is that a sort of constructive interference?

Brandon Sanderson

Constructed? No. Resonance is more about the way-- It's more of a natural interference.

Questioner

So what I mean like, you have two waves, right? And if their troughs, you know--

Brandon Sanderson

Okay, is that the formal term? For the constructed.-- Oh constructive? I thought you had said-- yeah. So yes, I would say that that is an accurate phrase. I mean obviously it's not exactly the same thing. But yeah, that's what I was looking at when I was building it, was kinda things like this with waveform patterns and whatnot. So yes. At least, it was inspired by this kind of idea.

Salt Lake City signing (Dec. 16, 2017)

Now you might be able to argue that the wielder is "channeling" investiture from the Shardplate, but that isn't the case from the Shardblades. The shardblades don't pass any investiture into the wielder, they fuel themselves with it instead. So even if Shardplates count, there's no countervailing "wave" from the Shardblade to enable the resonance in the first place.

In addition to this, though this is less of an issue with the cosmere and more from a plot standpoint, Sanderson has stated that the second half of the cosmere eras are going to be shifting to more and more mechanical uses of investiture rather than being 90% standard invested arts, as they are now. A great example of this is seen in the way spaceships are shown to work, and the Sunlit man - the only "invested art" (and I hesitate to call it even that) on Canticle is the ability to transfer heat. Anything more than that requires manipulation of the Sunhearts to either supercharge a body with investiture, or to fuel various devices. Given that, I don't know if he necessarily wants to run with mechanical uses of investiture generating Resonances.

We know that "raw" investiture - like the Mists - can be repelled under certain circumstances by investiture aligned with other intents. Vin needing to have the Hemalurgically charged earring removed before she could absorb the remnants of Preservations power is the perfect example of this - the Mists no longer enveloped her, the stronger the impact of Ruin became on the world and the stronger Ruin's intent became. It is not exactly a massive leap to extrapolate that if investiture is "charged" with an intent, that it is affected by the user's intent as a result in how easily it can be drawn upon.

Another good example of this is Kelsier taking up the power of Preservation using the jar of raw connection, in Secret History. We are shown that while - yes - he could slow down Ruin's destruction of the world in the same way as Vin did, as the connection faded - as the connection was weakened by his intent not aligning with Preservation, so too did his ability to restrain Ruin.

Finally, the Shards themselves have some rudimentary consciousness, even those shards that have been held uninterrupted since their formation. While Honor developed more, being "separate" and it's own entity for thousands of years, even with Odium we see that the Shard can be described as having it's own thoughts and ideas, in some way, and fights back or accepts the user.

All that to say - yes. I think that for a variety of reasons, the Shards and the Vessels need to be in alignment to bring forth the most power.

So, the issue with this is the only real time we've seen tones used to manipulate investiture is in the Stormlight archive, where it was used to draw investiture from one gem to another - and then to create anti-Investiture, to devastating effect.

However, no-one used those same reverberations to draw Stormlight (or Voidlight) from any of the Radiants or Fused in the Final Desolation. They had to use Raysium weapons, which acts as a conductor, and empty gemstones. Considering one of the sides of that conflict is built around the concept of Rhythms and Tones, the Singers, I doubt that if it were possible for them to steal Stormlight just by humming they wouldn't have passed that knowledge to every Singer to give them an edge.

And if they can't take Stormlight, one of the more volatile forms of Investiture (in that it dissipates from a living host quite quickly), I doubt they could forcibly steal a Breath.

On 1/18/2026 at 3:24 AM, Trusk'our said:

I wonder, would repeated exposure just Invest it more, or would it also physically expand the Sunheart? Or, is it more explicitly tied to the physical body that was destroyed initially?

We know that the size of the Sunheart is somewhat defined by the innate investiture of the person being converted - but that it doesn't necessarily limit the amount of investiture being stored. The traveller from Roshar created a sunheart *notably* smaller than any Threnodite had due to the difference in innate investiture (interestingly, Zellion also commented that the traveller "likely" had breaths, which suggests that Breaths don't count) - and yet Zellion was able to siphon power into the "charged" sunheart to reduce the impact of the torment.

I don't think there's any concrete evidence either way, but considering the Sunheart we saw the Scadrians playing with was only identified as having an unusually high amount of investiture in it after it was touched, I doubt that they are expanded by having additional investiture in them.

48 minutes ago, Sythrin said:

Is infrared not too big for atoms? To see atoms i think you need smaller light than even X-ray.

You do, but I was giving a more "practical" way to achieve a way to see through (in a sense) solid objects.

5 hours ago, Trusk'our said:

 

I guess if you're a Savant and you have super-powered sight, maybe x-ray vision could be done. Maybe. 

 

You know what? It probably would work. It's cool enough Brandon would be likely to throw it in.

I think a potential way that this would be achieved more... realistically? Than X-ray vision (which would require a dense source of piercing radiation on the other side of whatever you're trying to see) would be infrared. Humans already have a reasonably accurate sense for temperature based on the skin, and infrared radiation is part of the visible spectrum. You're just using senses the human body has, just magnified and "tuned". 

Now, is this practical? Unlikely. A tineye would need to be a savant to remotely approach the level of intensifying necessary to be able to pull this off, and that's ignoring the fact that human L-cones tend to peak at around 560nm for the type of light they pick up the best - while infrared tends to hover around 800-900nm.

Then again, investiture is a hell of a drug - and I don't think it's beyond the range of possibility that a suitably skilled Tineye could enhance their sight to the point they could see the infrared spectrum and use that as a bootleg "x-ray vision".

Though, that does raise another question - we know that you can store different senses in a Tinmind. How far does the subdivision go? Smell and taste are inextricably linked but can be stored separately. Could you store your ability to see specific wavelengths of light? If so it would make this process significantly easier - because I imagine if you've pumped your vision to the extent where you're 50-60% out of your normal visible range of light, everything else might overwhelm the infrared. It's not even necessarily impractical - colours tend to be divided based on the cones, so you could filter based on cones.

That would be a weird Malwish medallion to create, but interesting.

32 minutes ago, Theory said:

How are the Shards/Vessels warped?

How are they not?

Look at Ati, for example. Holding onto Ruin for thousands of years changed him irrevocably, turning him from someone that Leras described as the best among them, and incredibly kind, to someone who took great pleasure in causing unimaginable pain and suffering - causing the eruption of a volcano to burn a village alive, among other things, and drove the inquisitors into frenzies of ecstasy when committing murders. The pure concept of Ruin, no matter how Ati justified it to himself by couching in terms of entropy, changed him - warped him.

The Shards are masses of investiture imbued with a single pure Intent, and that Intent changes the users (see Tanavast, for example) when the users don't align with the Shard. In a normal being or Adonalsium, those Intents would be restrained and tempered by the existence of all of the other Intents present (if they'd even be present in the same way, as we know the 16 we have aren't the only Intents that were possible to create in the Shattering).  But when on their own, there's nothing to hold them back - and thus, they end up warped, driven singlemindedly.

But the question is what does that mean for whatever Adonalsium comes from? It makes sense if they are inherently complete, because they are a balance of all 16 shards and the intents involved. The Shards and their Vessels are unbalanced by not possessing the complete whole of what made up Adonalsium, warping them in an incredibly extreme way - but from everything we know about Adonalsium, they didn't have those issues.

A 4th ideal Kandra is a moderately terrifying concept, but I think what interests me a bit more is how this would interact with Kandra Blessings. Hemalurgy doesn't necessarily repulse other investiture like it does to investiture with Preservation's intent, but would Shardplate be able to replace or replicate the effects of the Blessings by being worn internally?

I think the key thing to remember here is:

For a lot of magic systems in the cosmere, "Growth" in power isn't really a thing unless you become a Savant. You have a set level of power available to you, and you just learn how to use it better. Cases in point:

• Allomancers and Feruchemists are stated to not really improve in power, their capability is "set" from the start. Elend becomes, in terms of raw power, the strongest allomancer of his era (able to control Koloss without Duralumin where Vin needed to use Duralumin) after consuming the bead of Lerasium, while Vin was a much more skilled user of her powers which let her seemingly do more than he could. Spook grew in "power" with his tin after overusing it and becoming a Savant and we see him consuming more tin than others do - significantly more. Accessing more power.
• Sand Mastery doesn't really have an increase in power under normal circumstances. The number of ribbons one can control never changes unless you Overmaster, and go specifically beyond your limits (and thus pushing yourself closer to Savantism).
• On Sel, Elantrians are set in the level of power they control, they just get better at drawing Aons. Riina's power comes from being exceptionally good at drawing and "coding" with Aons, not from inherently being stronger than other Elantrians.

Nalthis is a little odd, but it's still more or less the same. You can learn to do more with the same amount of power - and you can acquire power from other people to also increase your own capabilities, but each person's individual capability barring breath is dependent on skill, rather than growing power.

The Radiant Orders are one of the few ways of organised access to a Manifestation of Investiture that grant a power increase as you improve. Going from barely able to control the investiture to being able to handle larger and larger amounts of power and express it in more and more explosive ways. 

High Ideal Radiants are probably about as close as we're ever going to get to seeing a Savant in a surge (beyond, specifically, the Soulcasting Savantism we see as a result of overusing Soulcaster fabrials). Their bond either mimics the effect of, or provides a controlled way to advance to a new stage of a state similar to Savantism.

On 12/9/2025 at 9:53 PM, The Unsoulcastable Stick said:

I have this question because in the book SLA it talks about how Larkin eat Investiture and the metal in scadrial is invested

 

It could also be that the Allomancer is the one to turn it into investiture although that is less likely because of the light that comes from metal when Vin is Preservation

 

Also this would mean that if you had a Larkin on scadrial then it could be one of the best ways to detect who is an allomancer

Regarding the second part of your question, though - the best way to detect an Allomancer on Scadrial is still to burn bronze, but any way of sensing kinetic investiture would work (read, any way of sensing investiture that is not in a passive state, like in a Feruchemist's metalminds). There are a couple of ways you could do this - the sand from Taldain is a good example, but Larkins would also probably be able to sense them. The downside being that it would be extremely obvious what you were doing, as Scadrial doesn't exactly have dog-sized insects flapping about the place on the average day.

Most of the time you're going to find it easier to just use white sand or, if you're a native Scadrian, just find a local Seeker and pay them (if you weren't a Seeker already).

But what about the anti-stickiness? Those who despise the stick and seek to cast it down?

6 hours ago, First of the Tide said:

It's a very complicated question. The two situations are pretty different. the way i understand it, Taln was tortured externally, whereas Marsh was controlled internally. Even though taln stood up against the torture for thousands of years without breaking, WaT Spoilers:

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He still never broke, Chanaranach died and then broke (Shallan's Mom)

That is more a matter of guarding the sanctity of your mind against outside forces, whereas Marsh had to guard his own mind against his own mind (which I think he did by not thinking abt what he was doing but I don't know for sure) Also, marsh's main drive to resist, in this situation imo was his connection to all the relevant things (He doesn't want vin to die, if he resists the world of the peeps he loves keeps going, etc) taln wouldn't have that personal connection automatically to Scadrial. Both exhibit incredible will power, but beside individual skills as well. I think Taln could def. do the willpower part, and could prob. pull off the connection bit, since he kinda did that anyway in SA, even tho he didn't know those peeps, but  I don't think he's clever in the way that would be required to subvert his own mind

It's not even torture, per se. Marsh wasn't "tortured" mentally by the spikes, Ruin was literally overriding his thoughts - making him take perverse glee in the act of carnage, of spiking, or murder.

The issue is that the spikes, as stated earlier, both crack the spiritweb (making holes for power to seep in, and thus making the sufferer more "controllable"), but they're also a direct feedback instrument to Ruin. Ruin's "side" of the power to communicate comes from being able to push at the cracks in someone's soul and let his voice be heard, in opposition to Preservation's ability to hear everything. It's why madmen can hear his voice - or the voice of cognitive shadows in general.

Taln's willpower is supremely strong, but this isn't torture. This is the force of a Shardic mind paying attention to someone and directly overriding their iown mind. Taln is incredible, but even he couldn't stand up to a shard forever.

In a peculiar way, Radiant Oaths are closer to meritocracy (but a very weird, stormed up type of meritocracy). 

Spren are attracted to those who have the potential to join a Radiant Order, and after a short while bond to them and help them progress. Squires are more likely (in some regards) to become Radiants, but even then it isn't guaranteed. But once you've been chosen, it's down to you. Your oaths bind you to acting in a way that is generally in the best interests of society (though Nale's Skybreakers and the Ashspren hating modern humanity and thus generally choosing Dustbringers who will act against the greater good show that that isn't guaranteed), and in order to gain more power you need to show greater adherence to your ideals and acknowledge your own growth of character.

On 11/17/2025 at 10:49 AM, Aekiel2 said:

Interesting thing to note.

The behaviour Dajer is trying to induce in the Dakwara is exactly how Nightblood behaves after eating too much Investiture.

This is likely more a reference to "things that eat other things in general" than implying nightblood is made of anti-investiture. While never explicitly stated, we know that (SA):
 

Investiture, especially a large enough quantity, is affected both by the thoughts of those around it and can become self-aware, after a fashion. As far as we're aware, that's what the Evil is - sort of self aware anti-investiture born from the splintering of Ambition over Threnody. The people on First of the Sun see the Dakwara as a giant animal protector god, which would shape this investiture seeking a form to match it more - in the same way they changed it to protect them and "obey the one who defeated it".

A thought occurred when I was reading through some WoBs;
 

The key part being that in his first response he comments that Feruchemy could be fuelled by external sources, such as the unkeyed Dor jar that the Ghostbloods used in TLM. This is logical, considering how we know that unkeyed investiture and manifestations of Investiture work in general.

But how does this manifest, exactly? My two major questions (as a connoisseur of Feruchemy, these questions are important to me for... reasons) are:

• How does a Feruchemist use unkeyed Investiture?
  • We know (also from TLM) that Allomancer Mistings using raw investiture from an external source, not burning metals, have that investiture channelled through their Allomantic power  that they manifest, and in the case of Vin/Elend that if you are a full Allomancer drawing on external investiture you can channel it as you choose (Push/Pull, Pewter etc.).
  • It's likely this would work for some things, and wouldn't for others. F-Copper, for example, likely wouldn't be able to be drawn by a Feruchemist from unkeyed investiture because it seems to work much more like some other examples of "memories stored in investiture" that we've seen so far, in that there needs to be actual memory woven in to the investiture - you'd probably just get a jarbled mess of nothing, or maybe the "tone" of the investiture? But F-Pewter is a much more straightforward explanation - you just convert it directly into the attribute you want through your power.
  • Do you, then, need the investiture to be placed in your metalminds? Or can you "digest" it directly? Allomancy is meant to process investiture directly drawn from Preservation, so it makes sense that it can filter unkeyed investiture through whatever power they use. Feruchemists, though, are only seen to be drawing/replacing investiture from their metalminds rather than processing it internally, necessarily. Can we assume it works like Allomancy, or does it need to be shaped by the metal?
• Could you use unkeyed investiture to make unsealed metalminds?
  • The Excisors were user originally to make unsealed metalminds for the Southern Scadrians so they could share heat, but as we now know Harmony's Perpendicularity is not only located in the Malwish empire but is also "closely guarded" - enough that Autonomy didn't want to send her army through it to preserve it's strength. With relatively easy access to a source of nominally limitless investiture, can they fill their unsealed metalminds with it? Could this explain the (frankly, ridiculous) power they will eventually need come the future of the Cosmere?

Without getting into the weeds of how unkeyed investiture could fuel each individual ability too much, a full Feruchemist who was able to fuel themselves with unkeyed investiture is just a fascinating concept - the conversion rate, how fast the investiture would drain, there's so much interesting to learn. 

This may in fact be spawned by my suspicion that that is exactly how the Bands of Mourning were made, why they drained quite as fast as they did, and why they were drained by TLM.

9 minutes ago, Treamayne said:

Honor did not "design" the Radiant Ideals or even the way that True Spren form Radiant Bonds. MoIs are a result of the complex interaction of the Shard's Intent, the Planet's Identity and the Cognitive Concenssus of the inhabitants. Honor didn't "design" surgebinding (just limited it). WoB (Mistborn Spoilers):

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asmodeus

You've said before that a lot of the magics we see across the cosmere come from an interaction of Shards and their Investiture with the planets they Invest in. What does this mean practically? If Scadrial explodes tomorrow, will Hemalurgy stop working across the cosmere?

Brandon Sanderson

Hemalurgy wouldn't stop working, most likely, but it could. There are ways that you could make it stop working. I kind of mean that the Shards are an innate part of physics in the cosmere, and the magics that arise are an innate part of physics because of that. Like atium seeped out into the Pits of Hathsin, in the same way, these magics are just gonna leak out, and different places are going to affect them. You'll see Lightweaving happening in different places, and the way the Shard is interacting with the local... The way the Shard is is going to affect how Lightweaving is administrated in the various magics, but it's still gonna be there. Hemalurgy is kind of a similar thing to that. You will see Midnight Essence, you will see some of these recurring ideas popping up, and these are like natural parts of the physics, but they're influenced by the Shards on the local planets.

I don't know if that answer, that's gonna be a really fun one for them to transcribe into the Q&A thing, because I go around in circles on that question a ton. Put this part in when you do it.

Footnote: It was a really fun one.
YouTube Spoiler Stream 4 (June 16, 2022)

 

Ishar had much more involvement that Honor in manipulating the Rosharan Native Surgebinding that arose during the Desolations into the Radiant Orders (WaT Ch 59, WoR Epigraph)

I rather think you made my point for me there.

I never said Honor created surgebinding, just the Radiant Oaths - exactly in the way as you said. He was surprised by the bonds between between Spren and Man, yes, but as per WaT chapter 120 he also was the one (alongside Cultivation and Ishar) who created the system of Oaths that bound them. That's kind of the key to all of this - he didn't create the surges, I never said he did, but he did administer access and limit it. What is the Radiant Oath if not a way of imposing limitations?

The Epigraph you quote to me says much more that Ishar was responsible for the organization of the Knights Radiant as 10 military knightly orders - his ability to manipulate connection as the Bondsmith Herald definitely had a lot to do with the Oaths, but that doesn't preclude the system guarding access to the surges being designed to control the growth of Radiants in a way that can mirror the *effects* on the Spiritweb of Savantism.

1 hour ago, Treamayne said:

Now I am just extra confused. you seem to be arguing two opposiing things at the same time as if they were synonymous. 

• Savantism = Warping of the Spiritweb due to investiture
• Radiant Nahel Bond = Reinforcing the Spiritweb through investiture released by Oaths and Connection

The only thing they have in common is a modification of the Spiritweb (which is true of almost every MoI). To be clear, I am not saying you are drawing improper conclusions - I am saying you are using the wrong terms to describe them (or I am hopelessly lost in what you mean at all). After all (WoB Extract):

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Kind means similar, not same. Uncontrolled is at least one primary difference. Therefore

• Spren Bond =/= Savantism

I think you are taking a partial analogy description too literally. What little we know about Savantism indicates that it cannot be invoked by four short bursts of connection-released investiture - even if a Radiant somehow said Oaths 2-5 all in the same day. 

I feel you are missing my point.

Savantism, yes, warps the Spiritweb via investiture. This makes the Spiritweb more able to handle investiture, letting it either channel the investiture more efficiently or by channelling more of it - see Spook's increased senses beyond even normal Tineyes. The Radiant bond also changes the Spiritweb, but it does so in a controlled fashion, using the Spren to regulate the changes to the Spiritweb.

This is the core of my argument. The Radiant Bond was created (as I said) specifically as a way to control the progression of Savantism while allowing for the growth of power of the user.

I'm not saying that they're the same thing. I am specifically saying that the Radiant Bond seems to be an attempt to mimic the beneficial effects of Savantism - namely, the increased ability to hold and use investiture - without needing to suffer the negative effects as well - namely, the physiological warping thanks to the changed Spiritweb. We see that Savantism is generally harmful, and that that is what Sanderson wants to keep in spirit, with his comments regarding Wax's Savantism being too consequence-free. The Radiant bond, by contrast, provides a similar power boost and level of control each time you step up an Ideal while not having the same negative effect. 

The Radiant bond does not protect the user from Savantism - and yet, Radiants are explicitly affected by it differently. The two are distinct, but how does this happen?

Maybe it's because the process of Swearing the ideals, grafting the Spren more tightly to the Spiritweb of the Radiant, and using the rush of Investiture as a catalyst to drive the grafting, is explicitly designed to change the Spiritweb in a predictable, controlled way that makes it so that modifications that would manifest as Savantism have already happened in a controlled context without the negative side effects.

I feel you're focusing too hard on thinking I said that Savantism and the Radiant bond are the same thing explicitly.

On 11/10/2025 at 11:53 PM, Riino said:

Can't windrunners infuse the ground to prevent the Deepest Ones from using Cohesion to move through, effectively freezing the Deepest Ones in stone like what happened when the sibling re-awakened. Couldn't Kaladin use this in ROW to just freeze them?

 

"Cohesion is highly resisted by Investiture, and even a small amount of Stormlight in an object would prevent it from working." 

- Coppermind on Cohesion

Let me use the example of Ishar disabling the Windrunners to poke a hole in your theory:

Adhesion, when we've seen it so far, is less "infusing an object" and more connecting one object to another.  When we see him using it to attach himself to walls, it's small scale, and only really acts on the very surface to bond - say - a hand to a wall, or the soles of some shoes. Surface level, small-scale, and focused on a single area. 

To stop the Deepest ones you would need to infuse the entire surface of the rock at least, and that would be very difficult. Ishar created a connection - a different type, with Bondsmith powers rather than Windrunners, but still a connection with Adhesion - with the ground, making almost all the stormlight flood from them into the ground below.

17 hours ago, Trusk'our said:

I will say on the Fused though, they're supposed to be able to hold Voidlight indefinitely, so maybe with Leshwi and the other rebels Taravodium just pulled it away the same way Tetribution tried to drain the Spren.

Yea, I agree, that's why I specify "without a connection to Odium" - They are Cognitive shadows bound to his intent, but when he withdraws his connection to them they lose that intent and thus what lets them store it indefinitely. They definitely last longer without a refill on the trek from Urithiru to the Shattered Plains than a Radiant would holding Stormlight, though, from the description.

17 hours ago, Trusk'our said:

Have it fully keyed to you, often being in the form of your own Spiritweb. 

Allomancers have a larger, permanent piece of Preservation as a part of their Spiritweb, and it doesn't ever leave (unless, you know, Hemalurgy). Technically, anyone living on a Shardworld should have something similar permanently sewn into their spiritual makeup, albeit smaller. 

That's different from Stormlight, though. That investiture is, as you note, part of your spiritweb. Yes, you can't really untangle the physical, cognitive, and spiritual aspects of a being especially as far as investiture is concerned, but when Allomancers are burning metal they aren't "holding" the power per se, they're using it to draw out investiture from Preservation - it's "streaming" investiture rather than stockpiling it, gaining to be used immediately. We see at the end of TLM that Allomancers can use raw investiture to power their abilities but they don't hold it physically for that long before it starts to hurt them. 

Similarly, usage of the Dor uses characters of some description, to open windows into the cognitive realm and shape the effects of the Dor through those windows (Dakhor, AonDor, Forging, even ChayShan seems to do so through the symbolism of their rotation). Examples like the Luhel bond don't involve the user holding investiture as much as it does exchanging water for control via symbiotic bonds with the thing actually doing the work.

I suppose my point here is that  the only MoIs I am aware of (and I am entirely willing to be proven wrong here) that seem to directly involve storing investiture within the body for a relatively extended period are those on Roshar, Nalthis, and Taldain with Starmarks specifically storing energy form the smaller star that the Darkside faces. And of those, none of them have "perfect" storage in a physical mortal body - Breaths are partly bonded to the spiritweb through Endowment's intent, though that bond can be broken and at least in part the investiture is present physically too, Taldain Starmarks are more like tattoos so the investiture there is almost closer to storing in a medallion/metalmind, and on Roshar the investiture wants to escape to fuel the ecosystem.

We know it's possible to store investiture for an arbitrarily long time given the correct prison (Ba-Ado-Mishram), and without binding the investiture to the spiritweb I'm just wondering what it would take to actually turn a mortal body into a "perfect" prison a la a perfect gemstone.

17 hours ago, Treamayne said:

Unlikely. As you say, the leakage from the Spiritual Realm as an Oath is sworn is short and fast and infrequent. Savantism takes a long time. Kaza was soulcasting weekly her whole adult life, and only started losing parts to smoke fairly recently (a few years). Mistborn Spoilers:

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The fastest example seen was Hero of Ages (further Spoilers)

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Spook was Flaring Tin every waking hour of every day for a year before he started seeing physiological changes to his body by the warping Spiritweb. 

 

Hope that helps

I want to clarify here I'm not saying that it is exactly the same as raw, uncontrolled Savantism of the kind Spook developed after flaring for a year. I do specify a "controlled" form of Savantism because that's exactly what the effects of the Spren bond seem to do, from the description of how we have of how Savantism and how the Radiant bond works.

Savantism is literally described by Sanderson as very similar to an uncontrolled spren bond (in fact, I'm going to borrow Trusk'our's quote here):
 

I suppose my point is more that I think it's very likely that this was an intentional choice in the construction of the Radiant sysem and the usage of the Nahel bond to mitigate the negative effects of becoming a Savant on the body. Radiants are often "broken" people, which lines up with traditional Cosmere wisdom that if you have cracks in your Spiritweb already it's easier for the investiture to latch on, and for you to connect to it.

Honor knew the risks of letting surges go unchecked. While we don't have direct confirmation of this anywhere, I'm pretty sure we know that the destruction of Ashyn took at least decades to come to a full head and the sky to be burnt. There's no confirmation that this came from Savantism (Division is a hell of a drug), but even without confirmation on this considering the knowledge that a Shard has it is not unreasonable to assume that they would be aware of what Savantism is and how it affects the spiritual aspect of a person. The Honorblades were bound by their link to Honor, but they couldn't guarantee that in the same way with the Radiants. What better way to guarantee their restraint than by forcing a state similar to Savantism through the Nahel bond, grafting investiture in stages to their spiritweb with a surge of connection to the spiritual realm and thus investiture to weld the extra investiture even more firmly?

Savantism is defined as the nature of the Savant's spiritweb being modified by the investiture flowing through it when they channel their Invested Art. A good example in-SA for this are Soulcasters - we know that the fact they begin to turn into the essence their bound fabrial has control over is the result of Savantism. Further, we also know from WoB that Savantism does affect Knights Radiant, but they're affected differently and in a "much less pronounced" way from certain effects of it by the Nahel bond:
 

So, here's the question:

Since:

1. Savantism is the result of excessive amounts of investiture flowing through the spiritweb of the user, forcing it to adapt in a way and often leading to physiological changes of greater or lesser impact (Soulcasters being a great example of the more extreme end).
2. The Nahel bond is what allows for the channeling of Investiture for an aspiring Knight Radiant, with each Ideal increasing not only the strength/amount of Investiture you can carry and use but how long your body can hold it before losing it.
3. Swearing an ideal gives the user and those nearby an extreme amount of Investiture that refills for a short while, empowering them and those around them to fight while functioning as a temporary font of Investiture similar to a Dalinar's perpendicularities.

Did Honor design the Radiant ideals by using the Nahel bond as a way to achieve a controlled form of Savantism?

Each Ideal sworn provides an inoculation, a heavy dose of Investiture, while also further bonding the paired Spren to your spiritweb. Welding extra investiture to your spiritual aspect is almost exactly like the definition of Savantism, but this time with the benefit of being done intentionally, in a way that has minimal detrimental impact on the practitioner.

Not only does the quantity and duration of held Stormlight increase with each level, but the skill at manipulating that Stormlight and your particular Surges often increases at the same time. The interesting part there is the "quantity and duration" part to me, because we know humans are "leaky" to Stormlight, partly as a result of its natural inclination to dissipate back into the atmosphere to fuel the Rosharan ecosystem and partly because there's something unique about the structure of gemstones that makes them much better at keeping the Stormlight trapped inside themselves.

The bond to a Spren patching the holes in the spiritweb that let Stormlight leak out so rapidly, the surge of investiture that acts as a fuel to drive the change, would line up with the descriptions of Savantism we know about, and it would also explain the comment about "if you have an active bond with the spren it takes a little different path".