How Would One Realistically Harness Hemalurgy?

[Trusk'our he/him]

Hemalurgy is very, very powerful, mostly due to its enormous flexibility- you could, in theory, use it to recreate or steal just about any other MoI. 

Unfortunately, that very flexibility makes it extraordinarily difficult to use, as unlike with a MoI with great rigidity like Allomancy, you can't create a construct or useful Spiritweb change by simply "activating" the magic. You need to be far more delicate to get something useful. 

To realistically harness Hemalurgy's broader abilities without the direct aid of a Shardic-level being, one would need a lot of knowledge. But, what would it actually look like to get that knowledge? 

For this thought experiment I'm assuming the person seeking to harness Hemalurgy has: 1. A pre-existing general knowledge of Hemalurgy and some of its uses, like Koloss transformations or Metalborn theft. 2. Financial backing and connections to get necessary tools for their operation. 3. No access to offworld MoI or Shardic intervention. 

First and foremost, you'll need a way to practice the art quite a bit. And while SR shenanigans should used, experimentation is almost certainly going to be necessary as well, just as Telsin's futuresight still required experimentation to get things right. So, you're gonna need a laboratory to test and center your operations. 

But where to start after getting a base of operations? It's true that the Steel Inquisitors had their own laboratories and didn't mind human sacrifice, but that kind of business model is unsustainable in the modern Era and is, quite frankly, revolting. 

A far more plausible method for experimenting would be to use a simpler animal, probably rats, in place of human test subjects. You can breed loads of them quickly to replenish your stock and can use them with far less moral cost. 

Rats actually share 90% of their DNA with humans, and are often used IRL to study diseases in humans due to their physiological and psychological similarity to us (at least that's what Google says). 

Obviously, they aren't exactly the same as us and we're also going to be using sDNA, not direct physical code, so successful Hemalurgy models in the rats may not be as compatible with humans as desired. Because of this you'll eventually need to try out Hemalurgy models on humans, but they should be well tested beforehand on the expendable rat subjects, and then maybe moved to terminally ill humans for stable models, and then humans who just want the spikes last. 

The first experiments, I think, should probably focus on the direct compatibility between rats and humans then. Koloss transformations I don't think would be hard to know of, given Allomancer Jak's stories, other's accounts of Koloss traditions, and of course the knowledge of the Hemalurgists that yes, seemingly magical transformations can occur with metal spikes. 

Sending out a group of researchers (probably Terris) who are willing to live alongside a relatively friendly Koloss tribe feels like the first real step to discover all the specific physiological and psychological changes made from their transformations. Plus, you can find out the placement of their spikes and send back the information to headquarters. 

After such, attempting to create a rat-Koloss feels like the next step to take in experimentation. If successful, you can use that knowledge to figure out the Bindpoint layout in humans vs rats, making it far easier for future rat testing to be useful. Plus, the Set were capable of modifying Chimera with a second spike, suggesting that tweaking a pre-existing model is more feasible than creating one from scratch (though Autonomy's or pseudo-Avatar Telsin's oversight probably helped), so modified versions of Koloss might be achievable with some work. 

This is good information, but still limits the use of Hemalurgy quite a bit. The Koloss model is potent, but has numerous drawbacks. Even improved Koloss- ones with milder or simply less debilitating changes- can really only do so much. 

Cognitive and spiritual augmentation should be practiced with as well, despite not having a base model to glean useful hints from. Still, if you have enough rats you might be able to start methodically trying out a number of spike combinations in the hopes of stumbling upon something useful. 

This is highly unlikely to yeild anything of value on its own due to its sheer complexity, given the Steel Inquisition's lack of success. So, this is where you can begin to try out SR hacks to jump forward in your research. Hiring a trusted Nicroburst and Oracles and possibly Augers could be useful for finding tricky spike positions, which you can then observe and record the changes wrought (Spinners are probably less useful for this area, as they have very finite access to their Investiture). 

Depending on your resources though, you might be able to have a scientist dip in Harmony's Shardpool and peek into the SR even more directly. This is highly dependent on whether you can get access to it (like if your organization is supported by the Ghostbloods), but if you can, it would be undeniably useful. 

Unsealed Metalminds might also be useful, depending on how versatile they are currently. Speed of thought, memory sharing, and Fortune would all be helpful if your scientists can get ahold of them. 

I think these steps can get you pretty far, but I think for the most specific, powerful transformations you will have to refine your spikes even further. We know from the existence of Kandra Blessings that it's not just the metal that matters, but what percentage and the specific parts of a Spiritweb that are taken. 

Spoiler

https://wob.coppermind.net/events/90-barnes-noble-b-fest-2016/#e4652

Questioner

What's the difference between a spike prepared for a Koloss and a spike prepared for a Mistwraith or Kandra? What side effects might occur from... [?]... Koloss spikes?

Brandon Sanderson

It's the pieces of the soul that are being ripped off and the amount of the soul that's being ripped off. That's a big part of it. What side effects would there be? You would probably not get something as intelligent.

Questioner

What's the difference in how you prepare those spikes?

Brandon Sanderson

The Koloss spikes, you've seen how they're done. The Kandra spikes were prepared by the Lord Ruler. He gave them to them, and so we don't know what he did, at least in canon.

Questioner 2

That means that we kind of screwed up the role playing.

Brandon Sanderson

You can totally do- I imagine all the role playing happening in a slightly different alternate universe, where there are slight variations and differences.

But yeah, there are no- Kandra spikes are prepared and given by the Lord Ruler, they didn't even know how to make them themselves. I mean they had an inkling of what went on, but they didn't know.

So experiments that begin utilizing Commands, alternative Bindpoints (assuming the heart is the de facto place to harvest attributes), and perhaps just more refined Intents to see if they affect models in a noticeable way should be implemented. 

Anyway, these are my current thoughts on how Hemalurgy could realistically be harnessed for future use. Additional thoughts?

Edited March 1, 2025 by Trusk'our

[Duxredux he/him]

Interesting... I have another significant direction that I think would be well worth exploring for this topic. What did Kel and Spook have that enabled them to make advancements in a matter of a few decades or centuries that was beyond the trial and error of the Steel Inquisitor laboratories? That said, TLR had good reason to not let any Inquisitor get too powerful lest they challenge him, so maybe some directions were curbed.

Let's look at what they had going for them. The obvious start is that Kelsier held Preservation and gained generalized insights into how Hemalurgy worked, starting from learning how Koloss were constructed. As a Cognitive Shadow, Kelsier could see the souls of people and hear their thoughts, and vitally see on the soul itself the placement of any spikes - including any changes visible during placement on the CR. I do wonder if Kel's insight that souls and metal are the same thing directly relates to Hemalurgy.

Next, I'm assuming they got permission or assistance from Marsh who would have been an incredibly useful reference for spike placement, material, and the knowledge that burning Atium lets you get the placement right. Early on while Marsh was young and didn't need to Compound age, they might have done just that. Not least, Marsh had performed several Hemalurgic operations under Ruin's control who had a far greater understanding than probably even TLR. This would let them get a head start on transferring Feruchemical powers.

Between Spook's Tin enhanced eyes, Marsh's Inquisitor sight and expertise with Bronze, and Kelsier's view from the Cognitive as a Sliver of Preservation, that's a dream team for drawing insights from Hemalurgy. Assuming of course we're excluding Kelsier's contacts with two of the best scholars we know, Sazed and Khriss. I do think Inquisitor sight and someone in the Cognitive also giving input on what each change did to the subject would be indispensable, particularly with the tech level they were starting at. As I'll describe later, I think their senses viewing a broad range of what was happening to the subject may have been a key factor to their discoveries. 

 

As for your current ideas for rat testing, there's some obvious limitations as it would be difficult to identify and isolate changes from anything outside of the physical attribute sector. Identity, memories, Connection, Invested powers, intelligence and more seem hard to test with rats. You might get some data by controlling them with the Flaw and putting them through tests but unfortunately some of the most useful Hemalurgic functions could really only be identified when performed on a sapient being. I don't see how rat tests would let you figure out how to steal Twinsoul's bond to Silajana even temporarily or Moonlight's transformed state. 

This unfortunately points towards Kel's idea of using criminals as Hemalurgic test subjects, which seems to have enormous potential to backfire as a comic book supervillain origin story.

 

In the end, I suspect what will be the biggest advancement in Hemalurgy is not the study of Hemalurgy but a study of Spiritwebs. Developing technology or abilities to see the anatomy of the soul will let you know what you are actually interacting with and what the Bindpoints map to. What we have seen up to this point seems more like science fiction horror from an era with only a vague understanding of anatomy, when lobotomies, amputation without anesthetic, blood letting, or trying to balance the internal humors were as much as we knew. Koloss and Inquisitors resemble the cultural iconic Frankenstein's monster not just little. Future Hemalurgy hopefully will resemble that monster as much as modern organ donations, transplants, brain surgery, and reconstructive operations resemble medieval surgery. Scadrial needs to learn more about the soul, not just blindly punch out pieces and cobble them together, counting on good Fortune to make it work. Now Hemalurgy can and will help with this in the same way that historically people who have survived being shot or impaled in the head have been tremendously useful for understanding the anatomy of the brain. This includes figuring out why the heart seems to be a universal donor point and why Metalborn power transfer Bindpoints function as they do. 

They are developing machines capable of using the Metallic Arts. I'd start looking at A-Steel, A-Bronze, or F-Duralumin in a finely controlled aluminum enclosed environment used to make something like an X-ray or MRI of the Spiritweb. That is a place that rats will probably be the first subjects. They are learning about spectroscopy and how different Investitures interact with each other. The biggest advancement might not come from someone studying Hemalurgy at all.

[Trusk'our he/him]

10 hours ago, Duxredux said:

Interesting... I have another significant direction that I think would be well worth exploring for this topic. What did Kel and Spook have that enabled them to make advancements in a matter of a few decades or centuries that was beyond the trial and error of the Steel Inquisitor laboratories? That said, TLR had good reason to not let any Inquisitor get too powerful lest they challenge him, so maybe some directions were curbed.

You know, given how TLR prevented Compounding and most Feruchemical powers for the Inquisitors, I think you have a good point.

I can't imagine TLR really pushing them to make new Hemalurgic constructs. Perhaps they took this initiative on their own?

11 hours ago, Duxredux said:

Let's look at what they had going for them. The obvious start is that Kelsier held Preservation and gained generalized insights into how Hemalurgy worked, starting from learning how Koloss were constructed. As a Cognitive Shadow, Kelsier could see the souls of people and hear their thoughts, and vitally see on the soul itself the placement of any spikes - including any changes visible during placement on the CR. I do wonder if Kel's insight that souls and metal are the same thing directly relates to Hemalurgy.

Next, I'm assuming they got permission or assistance from Marsh who would have been an incredibly useful reference for spike placement, material, and the knowledge that burning Atium lets you get the placement right. Early on while Marsh was young and didn't need to Compound age, they might have done just that. Not least, Marsh had performed several Hemalurgic operations under Ruin's control who had a far greater understanding than probably even TLR. This would let them get a head start on transferring Feruchemical powers.

Between Spook's Tin enhanced eyes, Marsh's Inquisitor sight and expertise with Bronze, and Kelsier's view from the Cognitive as a Sliver of Preservation, that's a dream team for drawing insights from Hemalurgy. Assuming of course we're excluding Kelsier's contacts with two of the best scholars we know, Sazed and Khriss. I do think Inquisitor sight and someone in the Cognitive also giving input on what each change did to the subject would be indispensable, particularly with the tech level they were starting at. As I'll describe later, I think their senses viewing a broad range of what was happening to the subject may have been a key factor to their discoveries. 

Hmm, that could prove valuable.

Perhaps Marsh's bronze Allomancy would have helped too, assuming that the Investing of spikes is comparable to Metalminds.

11 hours ago, Duxredux said:

As for your current ideas for rat testing, there's some obvious limitations as it would be difficult to identify and isolate changes from anything outside of the physical attribute sector. Identity, memories, Connection, Invested powers, intelligence and more seem hard to test with rats. You might get some data by controlling them with the Flaw and putting them through tests but unfortunately some of the most useful Hemalurgic functions could really only be identified when performed on a sapient being. I don't see how rat tests would let you figure out how to steal Twinsoul's bond to Silajana even temporarily or Moonlight's transformed state. 

This unfortunately points towards Kel's idea of using criminals as Hemalurgic test subjects, which seems to have enormous potential to backfire as a comic book supervillain origin story.

I think you could still glean some details from subtler attributes. It would take extra creativity, but some extra information would be extractable.

Though, yeah, I think it's unavoidable that some humans would need to bear spikes to see if the model worked. I still think terminally ill, willing subjects would be possible though. Just more scarce.

11 hours ago, Duxredux said:

In the end, I suspect what will be the biggest advancement in Hemalurgy is not the study of Hemalurgy but a study of Spiritwebs. Developing technology or abilities to see the anatomy of the soul will let you know what you are actually interacting with and what the Bindpoints map to. What we have seen up to this point seems more like science fiction horror from an era with only a vague understanding of anatomy, when lobotomies, amputation without anesthetic, blood letting, or trying to balance the internal humors were as much as we knew. Koloss and Inquisitors resemble the cultural iconic Frankenstein's monster not just little. Future Hemalurgy hopefully will resemble that monster as much as modern organ donations, transplants, brain surgery, and reconstructive operations resemble medieval surgery. Scadrial needs to learn more about the soul, not just blindly punch out pieces and cobble them together, counting on good Fortune to make it work. Now Hemalurgy can and will help with this in the same way that historically people who have survived being shot or impaled in the head have been tremendously useful for understanding the anatomy of the brain. This includes figuring out why the heart seems to be a universal donor point and why Metalborn power transfer Bindpoints function as they do. 

They are developing machines capable of using the Metallic Arts. I'd start looking at A-Steel, A-Bronze, or F-Duralumin in a finely controlled aluminum enclosed environment used to make something like an X-ray or MRI of the Spiritweb. That is a place that rats will probably be the first subjects. They are learning about spectroscopy and how different Investitures interact with each other. The biggest advancement might not come from someone studying Hemalurgy at all.

More excellent observations as always Dux.

The true benefits of studying Hemalurgy will probably come in the form of knowledge of the Spiritweb more than anything else.

 

I've also wondered recently, what would the final phase of Hemalurgy look like? If one can overcome the Flaw, unwanted warping of the Spiritweb, pain, harming donors, all of that- what is the actual end benefit?

My thinking is that you'd have complete control over all Spiritual aspects, and by virtue near total autonomy over your own being. Some pieces of the cognitive aspect, like individual memories, cannot be directly affected via Hemalurgy, but still, you could change yourself into virtually anything you wanted (especially with copper Feruchemy).

Is that. . . a good thing?

I mean, you could cut out all pain of disability, stubborn injuries, even change your appearance and mental/physical abilities to be whatever you wanted.

Which is great, but does that fundamentally undermine the process of individual growth?

I didn't expect to get philosophical talking about the soul, but maybe I should have.

[therunner he/him]

Quote

For this thought experiment I'm assuming the person seeking to harness Hemalurgy has: 1. A pre-existing general knowledge of Hemalurgy and some of its uses, like Koloss transformations or Metalborn theft. 2. Financial backing and connections to get necessary tools for their operation. 3. No access to offworld MoI or Shardic intervention.

With the above limits, I think you would do very little.

The Set had more than the above (Avatar, kidnapped Marsh, and right-hand Kandra of TLR) and it took them 2-3 decades at minimum to just discover that Intent affects Hemalurgy, and you might not have to kill donor (but the spikes created this way still don't work properly). So anyone working with even fewer information sources would take longer than that, more than half a century easily to even start making progress.

Starting from animal model might be useful to derive general properties of Hemalurgy, but would be of limited use for direct applications, as the spiritwebs and bindpoints will be too different. So eventually you will have to move on to human experimentation, and that will be ugly.

As Dux points out, studying spiritweb is likely the best, as afterall that is what you are manipulating.

7 hours ago, Trusk'our said:

I've also wondered recently, what would the final phase of Hemalurgy look like? If one can overcome the Flaw, unwanted warping of the Spiritweb, pain, harming donors, all of that- what is the actual end benefit?

I don't think either the Flaw or unwanted warping or harming of donors can be overcome, not fully. Hemalurgy is repeatedly stressed as always damaging, to both donor and recipient, and repellent to many other forms of Investiture.
 

• The Flaw is due to wide-open cracks in spiritweb, as Hemalurgy is smashing other pieces in. You might limit it, but those cracks will be present always because that is how Hemalurgy functions in the first place.
• Unwanted warping of spiritweb is also a result of Hemalurgy, as it it working around the unnatural addition. It might be limited with better knowledge of how to place spikes, and by placing weaker spikes, but some damage from the 'graft' will be present.
• Unwanted warping of bodies (for non-power spikes) also seems to be unavoidable, as it is likely result of the spiritweb modification expressing itself. You cannot have spiritually greater strength/better senses without your body changing to adapt to that.
• Harming donors is also unavoidable, at least temporarily, as you are literally ripping of parts of their soul. Even if Set non-killing spikes can be made to work, those people are diminished, and there is no guarantee they could heal that wound.

Pain is likely the one that could be diminished as advances in the anestesia appear. Though I would not be surprised if e.g. putting donor under led to sub-par spikes, as after all Hemalurgy is Ruinous art.

So I don't think Hemalurgy will ever get to that point, as it is being positioned as 'Power at a price (moral and physical as well)' kind of magic, and removing all drawbacks would not lead to good storytelling.

[Duxredux he/him]

On 3/1/2025 at 4:06 PM, Trusk'our said:

More excellent observations as always Dux.

Thanks for asking interesting questions! 

 

Hooboy. Philosophy time. 

Let's look at what has been said about Hemalurgy and Ruin. I can't help thinking that despite Ruin as a universal constant and a fundamental component of nature, Hemalurgy seems anything but natural. I can get where you see Ruin in nature, predators eating prey and taking the nutrients into themselves. Erosion and decay of the deceased as a necessary foundation for regrowth as larger complex structures are broken down and then consumed by lower level organisms. This is a primary component of how various elements like carbon cycle through an ecosystem. One of the main concepts at the end of both Era 1 and Era 2 is coming to peace with such things, as Sazed picks up Ruin in addition to Preservation and Wax storms the Set tower to stop Telsin. Accepting Ruin as a natural way of things, that it's okay if things change and come to an end, that seems like it can lead to healthier views on life.

How does Hemalurgy fit in? Hemalurgy fits the predation cycle, where the valuable attributes in the weak(er) or dying are consumed by the young or strong, yet that piece of soul is locked out of the rest of the cycle. It doesn't just follow patterns of life as it gets incorporated into the body and being, but the spike must be implanted into another soul, twisting and rerouting the body in the process. In most cases, once something dies, the physical, cognitive, and spiritual separate in their directions, yet with Hemalurgy that piece of soul is trapped for as long as the spike holds charge, just barely self-aware enough that it can be tricked into thinking it is still in a body so long as you keep it in a vat of blood. Should the spike lose its charge completely, Brandon has confirmed that piece of soul does indeed move to the Beyond. Presumably this means that a Hemalurgic spike loses its charge as the fragment of soul is pulled toward The Beyond, fighting the metal anchoring it to the Physical realm. This is more than a little disturbing, even if the only thing that you are doing is trying to excise a part of your own soul that you do not desire. 

That said, this is only half of what constitutes the art of Hemalurgy, which Brandon has divided into two distinct steps. Step one is the harvesting of a portion of a spiritweb into receptacle, the second is implanting an Invested spike into a Spiritweb. What we have seen in Era 1 and most of Era 2, is that getting what you want is greatly simplified if you use a known portion of soul as the Investiture for granting the powers. What I suspect we're learning from the Set experiments in TLM, with Moonlight's note that harvesting general Invested allowed them to briefly gain powers, is that any Investiture within the spike can be used to grant powers - the huge catch that they don't have a method to program the Investiture to do what you want it to. Existing soul fragments will just try to do what they used to do in their original soul, figuring out how to recreate that piece of soul is a non trivial issue.

Actually... from what your describe for hopes for late stage Hemalurgy, you're basically talking about Moonlight's final stamp that apparently they were uncertain would wear off. General Cosmere spoilers:

Spoiler

Okay, we know that was an Elantrian stamp, and after Shai took a huge jolt of Unkeyed Dor, she was able to rewrite up to and including where she was born, granting herself powers and Connections she would not have had naturally. In using an Essence Mark, the stamp sinks into the flesh until it contacts the soul, at which point it is locked into place. Essence Marks seem like a very logical method to program Investiture to make the exact changes to the soul that you want. Even then, the soul resists, causing the stamp to erode until the transformation ends and the soul reverts to the original state. What Hemalurgy seems to do is to not just overlay a secondary programming to the soul, but it jams in the piece of Investiture and shortcircuits the soul, prevent the soulf from resisting the change - in addition to reducing the ability for the soul to resist other external influences. Hemalurgy is basically forcing a hardwired exception to the soul's firewall with all of the issues that would have. 

People have asked what happens if you use a Hemalurgic spike on someone using an Essence Mark and we've been told it harvests the surrogate soul. What happens if you infuse an Essence Mark with Investiture and use the stamp itself as a Hemalurgic spike? It may be more complicated than this, but I now wonder if there may be a way to use Hemalurgy to make Essence Marks permanent. Even besides this, Shai had already engineered a method for an Essence Mark to remain indefinitely, her fifth Essence Mark back in ES that would have her restamp herself every 24 hours. The precision of both arts is what grants them flexibility - and the reversable Essence Marks allow for much greater experimentation on a single person without things going horribly wrong.

I suspect that late era will see much more ethical applications of coded Invested spikes that were not sourced from souls. Hemalurgy can create Connections never devised by the Shards and could potentially bring together planets and peoples from across the Cosmere. Medallion tech in general will be safer, particularly for things like Connection as we have already seen repeatedly used for language. One of Hemalurgy's main advantages is the permanence of it as it removes the soul's native ability to resist the change, allowing Kandra, Marsh, and Kel to benefit from their blessings for centuries. 

The darker side is of course harvesting souls for things that you can't fake or replicate. Connections that cannot be fooled, changes to a soul that can't come by any other way. General Cosmere spoilers:

Spoiler

Presumably this is why the Night Brigade is hunting Sig while he zig-zags across the Cosmere trying the keep his Connection to a Dawnshard out of their hands. When you need access to someone's Identity locked possessions, incredibly rare abilities, or when there isn't time to carve out an Essence Mark over the course of months or years, a metal spike can get the job done in a matter of seconds if you have the knowledge.

Yes, Hemalurgy warps the body and soul, but some conditions are congenital, and the soul's template may cause death. Take Professor Irich of the Set who presumably could not be healed even with unkeyed Feruchemical Health. It may not be that different from my friend who was born with congenital muscular dystrophy (CMD) who could not develop his muscles at all. Exercise simply hurt without building them back. He eventually needed metal rods fusing his spine and hips to keep him sitting up straight in his motorized wheelchair so that he did not lean over and collapse his lungs. Sometimes nature's healing (and presumably most Cosmere healing) can't fix it, so we do the best we can. For some people, being handed Allomantic Pewter for the first time without growing up with it, and it could break them, physically or egotistically, for some it may let them more or less live normally for once. This degree of remolding of the self is not that different from the ethics of plastic surgery (with one major caveat). I don't think very many people would begrudge a major burn victim or child born with a cleft lip from utilizing plastic surgery, but I expect there are some people turn to plastic surgery as a way to improve their self image and are never satisified with the results (while others probably take to it like a Kandra). All surgeries pretty much have to cut into the body and give it a chance to heal, we've just developed less intrusive ways of going about it. Is it natural to slice a person apart with a scalpel, peel back the rib cage, and install a pace maker before sewing them back together? Not particularly, but I'm okay with it. Less okay if someone wanted elective surgery for a second liver so that they could win drinking contests while others were on a waiting list.

That major caveat I mentioned though? I think there will always be a potential cost even if it is centuries later. If they figure out donorless elective seemingly ethical Hemalurgy for this kind of modification, it may be several generations before those Brandon's WoBs about Inquisitor children start becoming manifest. Spikes warp the body and soul, down to the DNA, and those heritable changes made the Inquisitors no longer Homo sapiens despite being able to breed with humans. He waffled on whether or not their children were more likely to be metalborn, but he did say that there could be complications. Those changes to the DNA and soul may not be fully traceable or understood by Scadrians for a very long time, and it may take Shardic intervention to reduce those complications as it did with the Koloss that were altered to breed true. It seems quite likely that we skipped over some really horrendous possibilities when the Koloss jumped straight from "designed sterile so they would die off" to "designed to breed true without complications". Circling back, these changes are exactly what you want those rat experiments for, but it seems plausible that with Moonlight's insights and stolen notes, they might figure out elective Hemalurgy before they figure out DNA.

In conclusion, rewriting the soul this directly in my opinion should never be done lightly or on a whim, but I won't write out some positive use cases with minimized (not eliminated) harm from Hemalurgy. Aluminum will mitigate the Flaw, donors may not be necessary for general operations, and they may be able to find the spike size thresholds to maximize benefit while minimizing the extent the body needs to warp around the spike. As for the alterations to the DNA... it's hard to say what would be better or what should be done for congenital defects and diseases, because those severe medical issues are already heritable, the spikes just add another layer of complication.

As a hopefully related aside for something I brushed on while poking around for this topic, I learned that stem cell research to grow replacement organs and tissues to supplement or replace the organ donation model, the stem cell grown organ may introduce a secondary set of DNA into the recipient. IRL there really is a thing called human chimerism where a person can have multiple DNA genotypes within their body which historically complicated a paternity test. I've barely scratched the surface there, so don't equate these operations with Hemalurgy, but the ethics of long term Hemalurgy are closer to the ethics of IRL medical advancements than you might think as we look at stem cell research and genetic modification.

 

WoBs:

Aluminum helping resist the Flaw

Spoiler

Questioner

The Lord Ruler used a lot of metal for shielding and stuff. But if he had had an aluminum helmet himself, would it have protected him from Ruin's influence at all, or would the spikes overcome that?

Brandon Sanderson

Aluminum helmet would help in that situation. Aluminum could very well have been something useful for resisting, yeah.

JordanCon 2021 (July 17, 2021)

Complications to Inquisitor children

Spoiler

zas678

You've said that Inquisitors could have children. Would those children have a better chance at being Allomancers compared to if they had the kids before they were Inquisitors?

Brandon Sanderson

Yes, but there also could be...complications.

/r/Fantasy_Bookclub Alloy of Law Q&A (Jan. 17, 2012)

Inquisitors no longer Homo sapiens

Spoiler

Axies (paraphrased)

Is Hoid human?

Brandon Sanderson (paraphrased)

Yes... but. Hoid is... you can say that he is still human, but his DNA have changed. Now he is human but you wouldn't call him Homo sapiens anymore. It happens something similar with the Steel Inquisitors

Barcelona signing (Nov. 3, 2016)

One caveat, this 2019 WoB Brandon says he's never been asked about Inquisitor children and that the spikes would not make them more likely to inherit the Metallic Arts genes, so... not sure where he's ended on this. I could believe that for the earlierWoB he might be thinking of genetic complications, for the later he might have been trying to make sure that Inquisitors with Feruchemy spikes could not have given birth to a Twinborn compounder in Era 1. Not sure.

Spoiler

Questioner

I wondered if an Inquisitor had children, if they would inherit stronger Inquisitor abilities, or if they would just inherit the lesser lines from being a Seeker, for example?

Brandon Sanderson

Excellent question. I don't think I've ever been asked this before... The way Hemalurgy works, if you're not aware, you are taking someone else's soul, and you are basically nailing it to your soul... That won't affect the children. So you will have the weaker lines.

They have tried that. Unfortunately.

Berlin signing (May 14, 2019)

Souls released from a Hemalurgic spike move to the Beyond

Spoiler

Dairetron

If a Hemalurgic spike loses its charge, does that mean the remaining part of the person's soul trapped will move on to the Beyond?

Brandon Sanderson

Yep.

Tampa Bay Comic Convention 2023 (July 28, 2023)

 

Edited March 3, 2025 by Duxredux
added WoBs.

[+robardin he/him]

The real advancement in "harnessing" hemalurgy (as of what we know at the end of Mistborn Era 2), IMHO, would be to facilitate the hot-swapping of spikes.

In his notebook on hemalurgy, Spook was already giving some thought as to how to ethically harvest Metalborn spikes, by "encouraging" people with Metalborn powers who were very old or with fatal conditions to "donate" themselves (basically, a Metalborn power donor program).

And given how Mistborn: Secret History ended, he was surely working with Kelsier at the time. So that knowledge and attitude, and access not just to Metalborn but wider Cosmere powers, are part of the Ghostbloods, from the top down and from the very beginning.

Meanwhile, we've seen that while creating a spike means killing the donor (as tearing off a core piece of someone's soul generally proves fatal), one can remove a spike and safely just lose the power (Spook pulling out his spike for pewter in Urteau). Or what Paalm was doing in Shadows of Self when she swapped a spike for F-steel (speed) for A-steel (Coinshot), though as a single trellium-spiked kandra, she might have been a special case.

So let's say the GBs do collect a little stash of hemalurgic spikes for various powers, and have found a way to preserve them without jars of blood. And the main thing to know about applying hemalurgy, once you've created the spikes, is "where the bind points are" to gain the proper effect from the matching spikes.

So why not pre-prep a little surgical sleeve or something at the right bind points, or just punctures like Vin's or Wax's earlobe pierced for an earring spike?

Fan theory holds that Wax's earring in Alloy of Law was a "very weak" spike for A-pewter that Harmony fueled directly with his mist, versus Vin's that granted her a doubling up of A-bronze. So maybe the earlobe is a general bind point, and earrings of various metals would allow for a little jewelry case of earrings granting different powers, or even one in each ear granting different powers?

And in fact, this fairly recent WoB (Nov 2023) suggests Hoid, at least, has achieved this, if the Ghostbloods have not (or have they?):

Quote

Questioner

If Hoid took lerasium in Mistborn: Secret History, does that mean his hemalurgic spikes are feruchemical?

Brandon Sanderson

What hemalurgic spikes?

Questioner

Hoid and his magic systems, he had hemalurgic spikes...

Brandon Sanderson

He does hold some. They may not be in him. Does that make sense? Hoid has hemalurgic spikes carried with him. ('Cause the people who asked me if Hoid has hemalurgic spikes didn't say which one.) He does not necessarily have them spiking him. He actually has, like, a little bandolier type thing. Hoid's got one of those with a bunch of spikes. He was gonna use them in one of the books, but it turned out to not be necessary, so I didn't put it in.

Dragonsteel 2023 (Nov. 21, 2023)

So Hoid has multiple spikes, doesn't always have one in him, and selectively chooses to use them.

Now THAT'S the future of hemalurgy!

[Trusk'our he/him]

1 hour ago, robardin said:

The real advancement in "harnessing" hemalurgy (as of what we know at the end of Mistborn Era 2), IMHO, would be to facilitate the hot-swapping of spikes.

In his notebook on hemalurgy, Spook was already giving some thought as to how to ethically harvest Metalborn spikes, by "encouraging" people with Metalborn powers who were very old or with fatal conditions to "donate" themselves (basically, a Metalborn power donor program).

And given how Mistborn: Secret History ended, he was surely working with Kelsier at the time. So that knowledge and attitude, and access not just to Metalborn but wider Cosmere powers, are part of the Ghostbloods, from the top down and from the very beginning.

Meanwhile, we've seen that while creating a spike means killing the donor (as tearing off a core piece of someone's soul generally proves fatal), one can remove a spike and safely just lose the power (Spook pulling out his spike for pewter in Urteau). Or what Paalm was doing in Shadows of Self when she swapped a spike for F-steel (speed) for A-steel (Coinshot), though as a single trellium-spiked kandra, she might have been a special case.

So let's say the GBs do collect a little stash of hemalurgic spikes for various powers, and have found a way to preserve them without jars of blood. And the main thing to know about applying hemalurgy, once you've created the spikes, is "where the bind points are" to gain the proper effect from the matching spikes.

So why not pre-prep a little surgical sleeve or something at the right bind points, or just punctures like Vin's or Wax's earlobe pierced for an earring spike?

Fan theory holds that Wax's earring in Alloy of Law was a "very weak" spike for A-pewter that Harmony fueled directly with his mist, versus Vin's that granted her a doubling up of A-bronze. So maybe the earlobe is a general bind point, and earrings of various metals would allow for a little jewelry case of earrings granting different powers, or even one in each ear granting different powers?

And in fact, this fairly recent WoB (Nov 2023) suggests Hoid, at least, has achieved this, if the Ghostbloods have not (or have they?):

So Hoid has multiple spikes, doesn't always have one in him, and selectively chooses to use them.

Now THAT'S the future of hemalurgy!

This seems like a very plausible use for Hemalurgy, at least for the power transference aspect.

Perhaps you could remove and implant small spikes with a kind of spring-loaded device lined with aluminum to prevent spike decay.

[ParaTulip fae/faer (declines as she/her)]

On 3/3/2025 at 6:59 AM, Duxredux said:

How does Hemalurgy fit in? Hemalurgy fits the predation cycle, where the valuable attributes in the weak(er) or dying are consumed by the young or strong, yet that piece of soul is locked out of the rest of the cycle. It doesn't just follow patterns of life as it gets incorporated into the body and being, but the spike must be implanted into another soul, twisting and rerouting the body in the process. In most cases, once something dies, the physical, cognitive, and spiritual separate in their directions, yet with Hemalurgy that piece of soul is trapped for as long as the spike holds charge, just barely self-aware enough that it can be tricked into thinking it is still in a body so long as you keep it in a vat of blood. Should the spike lose its charge completely, Brandon has confirmed that piece of soul does indeed move to the Beyond. Presumably this means that a Hemalurgic spike loses its charge as the fragment of soul is pulled toward The Beyond, fighting the metal anchoring it to the Physical realm. This is more than a little disturbing, even if the only thing that you are doing is trying to excise a part of your own soul that you do not desire. 

 

Since you brought this up under "philosophy time" I need to point out that this is using an argument from nature. What is natural need not be taken as good.

We have seen multiple characters decide that they actually don't want to go off to the Beyond. I have my own fiction I work on where I imagined a society that has nobles who inherit the memories of their ancestors, but in order to assume their full power they must bring about the death of the rest of their family, and this must be repeated in each generation or it will diminish them, and thus they tend to be few in number. I could imagine a line of Hemalurgists who pass a spike down their line, parent to child, hoping to give the next generation ever greater power at the cost of needing to exist without their parent and the pain of the transfer. Even without safe Hemalurgy, this would allow for the development of astounding amounts of capability without needing multiple spikes or anything complicated like that.

Sort of a cultivation of power over generations.