Question about Jezrien

[+mdross81]

So we’ve seen a total of 5 on-screen deaths involving Raysium daggers: Jezrien, Essu, Phendorana, Raboniel, and Lezian. For the last four, we have a pretty good understanding of the mechanics. The dagger was set to have anti-Investiture flow out, that anti-Investiture collided with and destroyed opposing Investiture, thereby killing three Fused and one honorspren.

With Jezrien though, there’s no anti-Investiture involved. His physical body is killed and his spirit (some combo of spiritual/cognitive aspects I think) was sucked into a gemstone through the Raysium dagger instead of returning to Braize via the Oathpact.

Kelek describes what happened next as follows:

Quote

The bond is what keeps us alive. You sever that, and we will slowly decompose into ordinary souls—with no valid Connection to the Physical or Spiritual Realms. Capture one of us with your knives, and you won’t be left with a spren in a jar, foolish ones. You’ll be left with a being that eventually fades away into the Beyond.

I felt it happen to Jezrien. You think you captured him, but our god is Splintered, our Oathpact severed. He faded over the weeks, and is gone now. Beyond your touch at long last.

I take it from the above that all that was left of Jezrien was an ordinary cognitive being that lacked the necessary Investiture to resist being pulled toward the beyond. And I understand the lack of a valid Connection to the Physical Realm.

But I’m wondering about the mechanics of the severing of his Connection to the Spiritual. I think it breaks down into two questions:

1. What exactly was the “bond” that was severed? The most likely candidate seems to be his bond to the other Heralds. But I suppose it could be to Roshar? Something else?

2. How was the bond severed? Was it the fact that what remained of him was trapped in a gemstone that severed the bond? That would seem undercut by what Kelek says about BAM. She was also trapped in a gemstone but, according to Kelek, would not fade, suggesting that merely being in a gemstone didn’t cut off her access to Investiture. (Maybe this is because Honor is dead but Odium is not)

Or was it something about being stabbed with a Raysium dagger? I assume that Jezrien’s being was still sufficiently linked with Honor’s Investiture when captured because Raysium conducts Investiture. So that seems to be how he was pulled into the gem (unless there was something special about the gem?).

Did the process of being pulled through Raysium sever the bond? One thing I’ve been thinking is that maybe Raysium acts as some kind of Spiritual Division. I found some evidence for this in the herald portraits in the arches in chapters in which Raysium daggers appear. In all but two chapters in which the daggers appear, either Nale’s or Chana’s (the two heralds with access to division) portraits are included. So this just has me wondering if the surge of Division is part of what severed Jezrien’s Connection to the Spiritual Realm. 
 

Interested in any thoughts. 

[LewsTherinTelescope]

6 hours ago, mdross81 said:

That would seem undercut by what Kelek says about BAM. She was also trapped in a gemstone but, according to Kelek, would not fade, suggesting that merely being in a gemstone didn’t cut off her access to Investiture.

That might just be a difference in how spren and Cognitive Shadows work, that perhaps CS need a fuel line of sorts while spren don't. 

[Kingsdaughter613]

10 hours ago, mdross81 said:

So we’ve seen a total of 5 on-screen deaths involving Raysium daggers: Jezrien, Essu, Phendorana, Raboniel, and Lezian. For the last four, we have a pretty good understanding of the mechanics. The dagger was set to have anti-Investiture flow out, that anti-Investiture collided with and destroyed opposing Investiture, thereby killing three Fused and one honorspren.

With Jezrien though, there’s no anti-Investiture involved. His physical body is killed and his spirit (some combo of spiritual/cognitive aspects I think) was sucked into a gemstone through the Raysium dagger instead of returning to Braize via the Oathpact.

Kelek describes what happened next as follows:

I take it from the above that all that was left of Jezrien was an ordinary cognitive being that lacked the necessary Investiture to resist being pulled toward the beyond. And I understand the lack of a valid Connection to the Physical Realm.

But I’m wondering about the mechanics of the severing of his Connection to the Spiritual. I think it breaks down into two questions:

1. What exactly was the “bond” that was severed? The most likely candidate seems to be his bond to the other Heralds. But I suppose it could be to Roshar? Something else?

2. How was the bond severed? Was it the fact that what remained of him was trapped in a gemstone that severed the bond? That would seem undercut by what Kelek says about BAM. She was also trapped in a gemstone but, according to Kelek, would not fade, suggesting that merely being in a gemstone didn’t cut off her access to Investiture. (Maybe this is because Honor is dead but Odium is not)

Or was it something about being stabbed with a Raysium dagger? I assume that Jezrien’s being was still sufficiently linked with Honor’s Investiture when captured because Raysium conducts Investiture. So that seems to be how he was pulled into the gem (unless there was something special about the gem?).

Did the process of being pulled through Raysium sever the bond? One thing I’ve been thinking is that maybe Raysium acts as some kind of Spiritual Division. I found some evidence for this in the herald portraits in the arches in chapters in which Raysium daggers appear. In all but two chapters in which the daggers appear, either Nale’s or Chana’s (the two heralds with access to division) portraits are included. So this just has me wondering if the surge of Division is part of what severed Jezrien’s Connection to the Spiritual Realm. 
 

Interested in any thoughts. 

Cognitive Shadows are similar to Spren in some ways, but they aren’t Spren.

A Spren is a splinter, a piece of Investiture become sapient. They are self-sustaining, as Investiture can only be altered, not destroyed. So being in a gem doesn’t kill them.

Shadows are Sapient minds or imprints of sapient minds granted an infusion of Investiture anchoring them to existence. Sever the chain and they go to the Beyond.

The question for me are Slivers. See, I think Slivers are sapient minds that have become Investiture. More so than Shadows then, Slivers would be Spren. A piece of sapient Investiture. We know that Slivers can persist indefinitely without external Investiture infusion, just as Spren do. And the terms Sliver and Splinter are fairly synonymous. If I’m right, a Sliver could survive in a gemstone. But I doubt Thaidakar is desperate enough to accept the risk just yet.

[+mdross81]

3 hours ago, LewsTherinTelescope said:

That might just be a difference in how spren and Cognitive Shadows work, that perhaps CS need a fuel line of sorts while spren don't. 

That’s possible, although there is WOB:

Quote

Oversleep (as Droga Królów)

Do the Heralds need to consume Investiture in order to stay in their body?

Brandon Sanderson

No. Good question. Excellent question. They're asking if they're like Returned and they need to consume a Breath each week.

Read For Pixels 2018 (Sept. 1, 2018)

 

[+mdross81]

1 minute ago, Kingsdaughter613 said:

Shadows are Sapient minds or imprints of sapient minds granted an infusion of Investiture anchoring them to existence. Sever the chain and they go to the Beyond.

Agreed. I’m just trying to tease out the mechanics of how the chain was severed in Jezrien’s case. 

[Ba-Ado-Fisherman]

10 hours ago, mdross81 said:

So we’ve seen a total of 5 on-screen deaths involving Raysium daggers: Jezrien, Essu, Phendorana, Raboniel, and Lezian. For the last four, we have a pretty good understanding of the mechanics. The dagger was set to have anti-Investiture flow out, that anti-Investiture collided with and destroyed opposing Investiture, thereby killing three Fused and one honorspren.

With Jezrien though, there’s no anti-Investiture involved. His physical body is killed and his spirit (some combo of spiritual/cognitive aspects I think) was sucked into a gemstone through the Raysium dagger instead of returning to Braize via the Oathpact.

Kelek describes what happened next as follows:

I take it from the above that all that was left of Jezrien was an ordinary cognitive being that lacked the necessary Investiture to resist being pulled toward the beyond. And I understand the lack of a valid Connection to the Physical Realm.

But I’m wondering about the mechanics of the severing of his Connection to the Spiritual. I think it breaks down into two questions:

1. What exactly was the “bond” that was severed? The most likely candidate seems to be his bond to the other Heralds. But I suppose it could be to Roshar? Something else?

2. How was the bond severed? Was it the fact that what remained of him was trapped in a gemstone that severed the bond? That would seem undercut by what Kelek says about BAM. She was also trapped in a gemstone but, according to Kelek, would not fade, suggesting that merely being in a gemstone didn’t cut off her access to Investiture. (Maybe this is because Honor is dead but Odium is not)

Or was it something about being stabbed with a Raysium dagger? I assume that Jezrien’s being was still sufficiently linked with Honor’s Investiture when captured because Raysium conducts Investiture. So that seems to be how he was pulled into the gem (unless there was something special about the gem?).

Did the process of being pulled through Raysium sever the bond? One thing I’ve been thinking is that maybe Raysium acts as some kind of Spiritual Division. I found some evidence for this in the herald portraits in the arches in chapters in which Raysium daggers appear. In all but two chapters in which the daggers appear, either Nale’s or Chana’s (the two heralds with access to division) portraits are included. So this just has me wondering if the surge of Division is part of what severed Jezrien’s Connection to the Spiritual Realm. 
 

Interested in any thoughts. 

How do we know that anti-investiture wasn't involved with Jezrien's death?

[AquaRegia]

22 minutes ago, Ba-Ado-Fisherman said:

How do we know that anti-investiture wasn't involved with Jezrien's death?

The Epigraphs from Kalak's journal (as noted above) make it quite clear that the Fused were trying to capture Jezrien, not kill him.  I suppose it's possible Kalak BELIEVES this to be the case, but is mistaken... but I think he is correct.

The dagger given to Moash by Leshwi is never described as having the anti-light glow or warping appearance, and he notes the gemstone is faintly glowing after the deed is done.

[Ba-Ado-Fisherman]

Just now, AquaRegia said:

The Epigraphs from Kalak's journal (as noted above) make it quite clear that the Fused were trying to capture Jezrien, not kill him.  I suppose it's possible Kalak BELIEVES this to be the case, but is mistaken... but I think he is correct.

The dagger given to Moash by Leshwi is never described as having the anti-light glow or warping appearance, and he notes the gemstone is faintly glowing after the deed is done.

Why would the Fused want to capture him if they could just destroy him?  Also, isn't the anti-investiture dagger Raboniel makes to kill her daughter very similar to the one Moash used?  If I remember correctly, they had to put an anti-investiture sphere into the blade, and it would be used up as they stabbed.  I'm guessing that the reason the gem glowed after Jezrien died is because there was a small amount of anti-investiture left in the gem.  Just my personal interpretation.

[+mdross81]

8 minutes ago, Ba-Ado-Fisherman said:

Why would the Fused want to capture him if they could just destroy him?  Also, isn't the anti-investiture dagger Raboniel makes to kill her daughter very similar to the one Moash used?  If I remember correctly, they had to put an anti-investiture sphere into the blade, and it would be used up as they stabbed.  I'm guessing that the reason the gem glowed after Jezrien died is because there was a small amount of anti-investiture left in the gem.  Just my personal interpretation.

I feel like there is conflicting evidence on this point. Here's the scene where the dagger first appears in OB 121:

Quote

“You have killed a king,” she said, removing something from a sheath within her robes. A strange knife, with a sapphire set into the pommel. The weapon was of a bright golden metal, so light it was almost white. “Would you do the same to a god?”

Leshwi seems to think that they're trying to kill Jezrien.

But on the other hand, there's no reference to any warping or weirdness about the sapphire, it's just described as a sapphire. Pretty much every time there's anti-Investiture in a gem, someone notes the strange warping. I suppose that could be because this is Moash's POV, and he just doesn't t care enough to remark on it.

Raboniel, who is perhaps not the most trustworthy source, also says that he goal was capture but that it went wrong:

Quote

“We use these for collecting the souls of Heralds,” Raboniel noted. “Or that was the plan. We’ve taken a single one so far, and … there have been complications with that capture. I had hoped to harvest the two you reportedly had here, but they left with your expeditionary force.”

Seems weird to me that she would have planned to harvest Ash and Taln using raysium daggers without anti-Investiture gems but that they would have an used anti-Investiture dagger with Jezrien.

[Ba-Ado-Fisherman]

Just now, mdross81 said:

I feel like there is conflicting evidence on this point. Here's the scene where the dagger first appears in OB 121:

Leshwi seems to think that they're trying to kill Jezrien.

But on the other hand, there's no reference to any warping or weirdness about the sapphire, it's just described as a sapphire. Pretty much every time there's anti-Investiture in a gem, someone notes the strange warping. I suppose that could be because this is Moash's POV, and he just doesn't t care enough to remark on it.

Raboniel, who is perhaps not the most trustworthy source, also says that he goal was capture but that it went wrong:

Seems weird to me that she would have planned to harvest Ash and Taln using raysium daggers without anti-Investiture gems but that they would have an used anti-Investiture dagger with Jezrien.

Raboniel clearly didn't have a full understanding of what exactly the dagger, or anti-investiture, does.  Perhaps they thought they could capture Heralds using it, but didn't realize it would destroy them completely instead.  There's definitely room for different theories though.

[AquaRegia]

The fact that both Kalak and Raboniel explicitly and matter-of-factly describe what happened to Jezrien as a "capture" ("collection", "harvest", etc.) makes me very confident that is exactly what was intended.  I find it very unlikely that Leshwi was not aware of this - otherwise, how would she have known to recover the knife with the now super-valuable-Herald-containing-gemstone in it?  What if Moash tossed it in a rock pile, or tried to keep it?  I think the obvious explanation is that Leshwi simply didn't want Moash to know that a "cognitive capture" was the actual objective, preferring for him (and us, as readers) to view it as a simple murder.  No Anti-Investiture was involved.

35 minutes ago, Ba-Ado-Fisherman said:

Raboniel clearly didn't have a full understanding of what exactly the dagger, or anti-investiture, does.

I don't think Raboniel had ever even HEARD of Anti-Investiture at this point.  Her first inkling that it exists comes from Navani's experiments later on.  She knew that the Raysium dagger would conduct Investiture, and that gemstones could be used to capture spren, and she really wanted it to work for Heralds.  She is later stunned by Navani's synthesis of Anti-Investiture, and sees it as a NEW way to end the war.

[Ba-Ado-Fisherman]

29 minutes ago, AquaRegia said:

The fact that both Kalak and Raboniel explicitly and matter-of-factly describe what happened to Jezrien as a "capture" ("collection", "harvest", etc.) makes me very confident that is exactly what was intended.  I find it very unlikely that Leshwi was not aware of this - otherwise, how would she have known to recover the knife with the now super-valuable-Herald-containing-gemstone in it?  What if Moash tossed it in a rock pile, or tried to keep it?  I think the obvious explanation is that Leshwi simply didn't want Moash to know that a "cognitive capture" was the actual objective, preferring for him (and us, as readers) to view it as a simple murder.  No Anti-Investiture was involved.

I don't think Raboniel had ever even HEARD of Anti-Investiture at this point.  Her first inkling that it exists comes from Navani's experiments later on.  She knew that the Raysium dagger would conduct Investiture, and that gemstones could be used to capture spren, and she really wanted it to work for Heralds.  She is later stunned by Navani's synthesis of Anti-Investiture, and sees it as a NEW way to end the war.

She didn't know what it was, but had seen it before, as in the dagger Moash had used.  She was using Navani to try and reproduce it after learning that it killed Jezrien for good, so she could end her daughter's suffering and hopefully end the cycle of Desolations.  Her previous knowledge and Navani's fresh pair of eyes discovered what it really was.

[+mdross81]

Jumping back to the mechanics of this (assuming that things went down as Kelek believed and that no anti-Investiture was involved in Jezrien's death), I'm thinking that it was possible to pull Jezrien's soul into the gemstone because his soul was infused with Investiture and raysium conducts Investiture.

Like, it wouldn't be possible to pull a regular, non-Invested person's soul into the dagger right?

If that's the case, then being stabbed with the knife did not immediately sever the Investiture from Jezrien's soul, because the Investiture is what allowed it to be conducted by the raysium into the gem.

But Kelek says that Jezrien's soul was left without a valid Connection to the SR. So either the process of being stabbed and pulled through the dagger, or the state of being entrapped within the gem must be the cause of severing that Connection.

If it's being pulled through the dagger that severs the Connection, then was only the Investiture pulled into the gemstone and Jezrien's cognitive aspect just went wherever normal, non-Invested cognitive aspects go on Roshar before being pulled into the Beyond?

Or if Jezrien's soul was pulled into the gem still Connected, what then caused the severing while he was trapped? Did the gemstone leak out the Investiture slowly because it wasn't a perfect enough gem? I'm just trying to nail down the process as much as I can. Maybe we just don't know enough yet.

[AquaRegia]

18 minutes ago, mdross81 said:

If it's being pulled through the dagger that severs the Connection, then was only the Investiture pulled into the gemstone and Jezrien's cognitive aspect just went wherever normal, non-Invested cognitive aspects go on Roshar before being pulled into the Beyond?

Or if Jezrien's soul was pulled into the gem still Connected, what then caused the severing while he was trapped? Did the gemstone leak out the Investiture slowly because it wasn't a perfect enough gem? I'm just trying to nail down the process as much as I can. Maybe we just don't know enough yet.

These are excellent questions, and I don't know enough to help pin down the answers.  My gut feeling is that the first item above is closer to the truth; we know an Invested Cognitive entity can persist for a while (before going to the Beyond) after all Connections are severed, and we also know that the Heralds do not require a constant influx of Investiture to continue existing.  So at this point I'd lean in favor of "the dagger severs a Spiritual Connection"... but I agree we have a lot to learn about both the process of trapping a spren in a gemstone and exactly how those Raysium daggers work.  Also, no, I don't think a regular non-Invested human would be affected in any odd way, just a regular old stabbing.  But I'd guess an Invested Radiant would be drained of Stormlight.

[Serack]

Skipping some of the responses sorry,

We don't know the mechanics of how the Heralds obtain physical bodies when they return from succumbing to pressure on Braise.  Dalinar's perceiving the bonds when he touched Nael demonstrated that their bond to the oath pact is already weakened except for Taln.  Presumably killing one with a weakened bond, with that knife, didn't just sever their connection with that physical realm body, but also with the pact that is somehow responsible for it and their immortality.  This may be a function of the aluminum itself, but more specifically of the aluminum siphoning off their "shadow" into the gem instead of to Braise as the oathpact usually did when they die.  

Edited January 27, 2021 by Serack

[LewsTherinTelescope]

5 hours ago, mdross81 said:

That’s possible, although there is WOB:

Based on what Zahel and Kalak say, this may be because they ordinarily have a sort of direct feed line. RoW 15:

Quote

“For the weaker ones, just kill the body again, make sure no one Invests the soul with more strength, and they’ll slip away in a few minutes. For stronger ones … well, you might be able to starve them. A lot of Type Twos feed on power. Keeps them going.

“These enemies of yours though, I think they’re too strong for that. They’ve lasted thousands of years already, and seem Connected to Odium to feed directly on his power.”

RoW 92 epigraph:

Quote

The bond is what keeps us alive. You sever that, and we will slowly decompose into ordinary souls—with no valid Connection to the Physical or Spiritual Realms.

With that cut, it seems like they decay over time, perhaps just like a certain other type of Shadow we've seen. 

Something of note: two Rosharan weeks is equal to approximately eight Cosmere standard days. It's plausible, then, that "over the weeks" in fact refers to around the same amount of time as a Returned lasts (though it's also plausible Jezrien lasted longer, as "weeks" is rather vague). 

 

4 hours ago, AquaRegia said:

I don't think Raboniel had ever even HEARD of Anti-Investiture at this point.  Her first inkling that it exists comes from Navani's experiments later on.  She knew that the Raysium dagger would conduct Investiture, and that gemstones could be used to capture spren, and she really wanted it to work for Heralds.  She is later stunned by Navani's synthesis of Anti-Investiture, and sees it as a NEW way to end the war.

Yeah, at this point she's still expecting Voidlight and Stormlight to destroy each other, right?

[Shob the Voidbringer]

i think that the fused didn't use anti-light for the dagger, but it just sucked his soul into the gemstone, but the difference between jezrians imprisonment and BAM's is that they used a bondsmith for BAM, possibly to connect them to the gemstone, so that they wouldn't fade away, but using raysium was unstable and severed connections instead of binding them to the gem

[+mdross81]

20 minutes ago, Shob the Voidbringer said:

i think that the fused didn't use anti-light for the dagger, but it just sucked his soul into the gemstone, but the difference between jezrians imprisonment and BAM's is that they used a bondsmith for BAM, possibly to connect them to the gemstone, so that they wouldn't fade away, but using raysium was unstable and severed connections instead of binding them to the gem

I had considered this as one of the biggest differences between BAM and Jezrien's situations, but forgot to include it in my original post. And you may be correct that the method of entrapment in the gems has a bearing on whether the being's Connection to the Spiritual realm is severed.

Given all of the talk about Adhesion being Honor's truest surge - unavailable to Odium's forces - it makes sense that they had to find another mechanism for trapping a Herald's soul.

[Kingsdaughter613]

9 hours ago, Ba-Ado-Fisherman said:

How do we know that anti-investiture wasn't involved with Jezrien's death?

Because the process for creating had yet to be invented.

More accurately, the Fused were unaware of the process that had been invented as that process has seemingly been lost. Navani reinvented the process, leading to the Fused gaining access to anti-light.

[Ba-Ado-Fisherman]

16 hours ago, Kingsdaughter613 said:

Because the process for creating had yet to be invented.

More accurately, the Fused were unaware of the process that had been invented as that process has seemingly been lost. Navani reinvented the process, leading to the Fused gaining access to anti-light.

Uhh, anti-investiture existed before Navani learned how to create it... Gavinar literally had a sphere of it 6 years before Way of Kings.

[Kingsdaughter613]

10 minutes ago, Ba-Ado-Fisherman said:

Uhh, anti-investiture existed before Navani learned how to create it... Gavinar literally had a sphere of it 6 years before Way of Kings.

A process that was lost, which I already noted:

“More accurately, the Fused were unaware of the process that had been invented as that process has seemingly been lost. Navani reinvented the process, leading to the Fused gaining access to anti-light.”

[Crucible of Shards]

It’s probably important that when Moash stabbed Jezrien and the gemstone began to glow softly, Ash IMMEDIATELY knew that something was wrong. And she didn’t just faint, she knew WHY she was fainting. The Connection was severed at that point.

[+mdross81]

5 minutes ago, Crucible of Shards said:

It’s probably important that when Moash stabbed Jezrien and the gemstone began to glow softly, Ash IMMEDIATELY knew that something was wrong. And she didn’t just faint, she knew WHY she was fainting. The Connection was severed at that point.

I tend to think that's right. Ash feels it and Taln just passes out completely. Here's the scene from OB, Chapter 121.

Quote

Ash stopped in place as something ripped inside of her.

Oh, God. Oh, Adonalsium!

What was that? What was that?

Taln whimpered and collapsed, a puppet with cut strings. Ash stumbled, then sank to her knees. She wrapped her arms around herself, trembling. It wasn’t pain. It was something far, far worse. A loss, a hole inside of her. A piece of her soul being excised.

“Miss?” a soldier asked, jogging up. “Miss, are you all right? Hey, someone get one of the healers! Miss, what’s wrong?”

“They … they killed him somehow…”

“Who?”

She looked up at the man, tears blurring her version. This wasn’t like their other deaths. This was something horrible. She couldn’t feel him at all.

They’d done something to Jezrien’s soul.

“My father,” she said, “is dead.”

Kelek also mentions feeling Jezrien being ripped away. On a side note, I'd really love to know what further investigation Kelek did to conclude that, although the Heralds felt him ripped away immediately, it actually took several weeks for his soul to fade away.

But back to the main topic, this is why I'm of the opinion that it was something about Jezrien's soul being pulled through the raysium dagger that actually severed his Connection to the Spiritual Realm. That spiritual Connection gets severed right away, leaving just a normal cognitive being - albeit one that had been highly Invested enough that it stuck around for some time before being pulled into the Beyond.

I think that a raysium dagger (perhaps needing to be accompanied by the right Intent) can cause Spiritual Division.

It think this Division might even be at play for the Fused deaths that involved anti-Voidlight. Maybe you need the raysium dagger to sever the Voidlight from the Fused's soul before it can be destroyed by the anti-Voidlight. If only Navani could run an experiment for us by trying to push anti-Voidlight into a Fused through some means other than a raysium dagger.

[Ba-Ado-Fisherman]

23 hours ago, Kingsdaughter613 said:

A process that was lost, which I already noted:

“More accurately, the Fused were unaware of the process that had been invented as that process has seemingly been lost. Navani reinvented the process, leading to the Fused gaining access to anti-light.”

The process wasn't lost completely.  I'm almost certain that some Fused, such as El, knew exactly how to create it, seeing as he had a dagger to kill the Pursuer (Defeated).  I'm guessing that Rayse saw anti-investiture as much too risky to use against the Radiants, so he either destroyed or trapped any Fused that had the knowledge, such as El.  I'm also guessing that El was punished and had his Rhythms taken from him precisely because he used anti-investiture against Rayse's will.  

 

Also, the Fused have to know how to create it for narrative reasons.  Raboniel knew, but now she's dead.  This would leave the humans as the only ones with the knowledge to create it.  Now that Taravangian holds Odium, I think he's going to release Fused such as El, and probably others, to create anti-investiture and end the Desolations in order to be released from Roshar.  

[Kingsdaughter613]

50 minutes ago, Ba-Ado-Fisherman said:

The process wasn't lost completely.  I'm almost certain that some Fused, such as El, knew exactly how to create it, seeing as he had a dagger to kill the Pursuer (Defeated).  I'm guessing that Rayse saw anti-investiture as much too risky to use against the Radiants, so he either destroyed or trapped any Fused that had the knowledge, such as El.  I'm also guessing that El was punished and had his Rhythms taken from him precisely because he used anti-investiture against Rayse's will.  

 

Also, the Fused have to know how to create it for narrative reasons.  Raboniel knew, but now she's dead.  This would leave the humans as the only ones with the knowledge to create it.  Now that Taravangian holds Odium, I think he's going to release Fused such as El, and probably others, to create anti-investiture and end the Desolations in order to be released from Roshar.  

El knew because Raboniel sent a copy of their studies to Kholinar.