Creation of Compounders?

[Riino He/Him]

Quite a bit of theorising here, without much research, but I think that you could create a twinborn.

If an Iron Feruchemist were stabbed with an Allomantic Iron spike, wouldn't the person become a Twinborn and also be a Compounder?

If this did work, then how would they be able to compound, because Hemalurgic Allomancers don't burn their Allomantic metal, would they have to be spiked with more Hemalurgic Iron, or would they just be able to ingest more Iron?

[Trusk'our he/him]

23 minutes ago, Riino said:

Quite a bit of theorising here, without much research, but I think that you could create a twinborn.

If an Iron Feruchemist were stabbed with an Allomantic Iron spike, wouldn't the person become a Twinborn and also be a Compounder?

This was the prevailing thought process pre TLM, but Marsh comments on how Identity contamination prevents modern Hemalurgy from allowing the creation of Compounders.

How Marsh bypasses this limitation is currently unknown. 

25 minutes ago, Riino said:

If this did work, then how would they be able to compound, because Hemalurgic Allomancers don't burn their Allomantic metal, would they have to be spiked with more Hemalurgic Iron, or would they just be able to ingest more Iron?

It sort of depends on the type of spike used.

Attribute spikes- things like human strength- provide a permanent stream of effect, no additional metals required. Kandra Blessings like TenSoon's stolen iron spikes are a good example of this.

Allomantic and Feruchemical powers granted via Hemalurgy function nearly the same, requiring the storing of attributes or the ingestion and burning of metals.

[Duxredux he/him]

@Trusk'our covered the general answer well, I'll do a deeper dive on the mechanics as we understand them.

To answer if this makes a Twinborn, basically yes. Compounding has a question mark though. Compounding when one of the powers is Hemalurgically granted runs into an issue known as Identity contamination. Because the power is routed through the piece of soul that has been grafted onto the Spiritweb, the ability presumably has Identity restrictions based on the grafted soul. While in the given scenario the Feruchemical power is natively keyed to the user, it doesn't match the Identity of the soul providing the Allomantic power - meaning it may not be possible to burn the metal to get Feruchemical attribute. 

Let's swap the powers and look at it again. What if a Lurcher gains a spike granting F-Iron? The spike lets them store and tap weight, but all of that is again routed through the fragment of soul. The storage will have the Identity of the original Feruchemist, which is why the Hemalurgist will be able to access the existing stores of the donor. This Identity will not match the Hemalurgist when they go to burn the metal Allomantically - the power isn't going through the grafted soul.

As @Trusk'our notes, we don't know how Marsh works around this, but it is possible - though considering Marsh has 22 spikes, his method may be impossible for our one spike Hemalurgist.

[Riino He/Him]

4 hours ago, Duxredux said:

@Trusk'our covered the general answer well, I'll do a deeper dive on the mechanics as we understand them.

To answer if this makes a Twinborn, basically yes. Compounding has a question mark though. Compounding when one of the powers is Hemalurgically granted runs into an issue known as Identity contamination. Because the power is routed through the piece of soul that has been grafted onto the Spiritweb, the ability presumably has Identity restrictions based on the grafted soul. While in the given scenario the Feruchemical power is natively keyed to the user, it doesn't match the Identity of the soul providing the Allomantic power - meaning it may not be possible to burn the metal to get Feruchemical attribute. 

Let's swap the powers and look at it again. What if a Lurcher gains a spike granting F-Iron? The spike lets them store and tap weight, but all of that is again routed through the fragment of soul. The storage will have the Identity of the original Feruchemist, which is why the Hemalurgist will be able to access the existing stores of the donor. This Identity will not match the Hemalurgist when they go to burn the metal Allomantically - the power isn't going through the grafted soul.

As @Trusk'our notes, we don't know how Marsh works around this, but it is possible - though considering Marsh has 22 spikes, his method may be impossible for our one spike Hemalurgist.

Thanks for the deep dive. This does make sense, but wouldn't unkeying the Feruchemical Metal Mind cause the Hemalurgist to be able to burn the metal, and if the Hemalurgist puts some of their own F-Attribute into the spike, wouldn't that also allow compounding?

[Trusk'our he/him]

7 hours ago, Riino said:

Thanks for the deep dive. This does make sense, but wouldn't unkeying the Feruchemical Metal Mind cause the Hemalurgist to be able to burn the metal,

As far as we can tell right now, any Allomancer- even one without Feruchemy- could Compound an Unkeyed Metalmind (though you can't store the extra attribute without Feruchemy. You'd essentially get a boost to the Feruchemical attribute while burning the Metalmind, but with a limited range of effect).

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and if the Hemalurgist puts some of their own F-Attribute into the spike, wouldn't that also allow compounding?

No, it won't.

It's an excellent idea, but apparently the Hemalurgist's own Identity muddies the original. This can also prevent two Hemalurgists sharing power from a single Feruchemist from sharing their own Metalminds with each other, but the principle is similar to that of Compounding- the original Feruchemist's Identity doesn't match the Allomantic component they have, which is likely what prevents Compounding via Hemalurgy (currently).

Spoiler

https://wob.coppermind.net/events/98-worldbuilders-ama/#e872

Lucadaw

If someone used Hemalurgy to take someones Feruchemical abilities would they be able to use that persons personal metalminds? Most relevantly perhaps to take that person's knowledge from their copperminds?

Brandon Sanderson

Yes.

Lucadaw

If someone stored their identity in an aluminium metalmind, then had their powers and metalminds stolen via Hemalurgy, then the person who took the powers used the aluminium metalmind to draw out the first persons identity would it permanently overwrite their personality with the original persons ? ( would kind of be a long winded way of stealing someone else's body and becoming immortal )

Brandon Sanderson

All Identity questions are a RAFO until I deal with it more in the books. (Sorry.)

WeiryWriter (in response to the first answer)

If the spike granting Feruchemy were to be reforged/split into two distinct spikes which are then implanted into two different people, could those two people "share" a metalmind (as in actually be able to tap something the other stored and vice versa?).

Brandon Sanderson

It's complicated, but no.

There would be too much of the other person mixed in. Both could use the metalminds of the person the Feruchemy was stolen from, but when they made their own, their own Identity would "muddy" the creation.

 

[Duxredux he/him]

6 hours ago, Riino said:

Thanks for the deep dive. This does make sense, but wouldn't unkeying the Feruchemical Metal Mind cause the Hemalurgist to be able to burn the metal, and if the Hemalurgist puts some of their own F-Attribute into the spike, wouldn't that also allow compounding?

Good questions. 

Let's start with Unkeying. While we never see this done on page, Wax and VenDell propose that if a Feruchemist were to have F-Aluminum in addition to their other powers, they could entirely store away their Identity. Once they had no Identity, they could then store another attribute that would also have no Identity. This results in an Unkeyed Metalmind. We've seen one Unkeyed Metalmind, a Goldmind taken from Lady Kelesina in BoM. Wax was unable to access the power while Wayne could. That's the distinction between Unsealed and Unkeyed Metalminds: anyone can use an Unsealed Metalmind, whereas only a Ferring with the matching power can access an Unkeyed Metalmind.

Back to our hypothetical Hemalurgist, getting a unkeyed weight storage is not straightforward at all. By Era 2 there are no natural born Feruchemists with more than a single power. With known Elendel tech, it would require Hemalurgy to pair F-Aluminum with any other Feruchemical power. The Southerners likely have a solution, but anything past this point is theory crafting.

As @Trusk'our notes (ninja'd again), any Allomancer can Compound using an appropriate Unkeyed Metalmind, as the Feruchemical storage "reprograms" the metal. When an Allomancer burns a metal, the metal itself does not contain the power, it acts more like a key that draws Investiture from Preservation in the form specified by the key. Burn Pewter and the Investiture drawn is configured to enhance the body. When burning a Metalmind, Preservation accepts the Feruchemical storage pattern as a valid key and returns raw power in the same form as the stored attribute. This is Compounding and is almost always paired with storing the new attribute and repeating the process.

I don't know if it has ever come up if Allomancy is Identity keyed, meaning the power drawn from Preservation is keyed to the Allomancer, but if it was this is when it would start causing issues. I don't see why it would be keyed, but I also don't see why it wouldn't.

[Isilel]

14 hours ago, Trusk'our said:

How Marsh bypasses this limitation is currently unknown.

 

Wasn't it strongly hinted that it was for the same reason as why his soul and those of pre-Catacendre folks in general could accept far more spikes than those of the Second Era? I.e. that Ruin was pushing on souls much more heavily back in Era 1 and hemalurgy was stronger?

 

2 hours ago, Duxredux said:

any Allomancer can Compound using an appropriate Unkeyed Metalmind

 

IIRC we don't actually know if Allomancers burning unkeyed storages would get the 8x(?) amplification of the attribute stored that natural Compounders get or just the same amount as stored, delivered at the rate of burning speed of a given metal. IMHO, the latter is more likely, since the former would be too overpowered.

[Duxredux he/him]

43 minutes ago, Isilel said:

Wasn't it strongly hinted that it was for the same reason as why his soul and those of pre-Catacendre folks in general could accept far more spikes than those of the Second Era? I.e. that Ruin was pushing on souls much more heavily back in Era 1 and hemalurgy was stronger?

Source? As it is, one way or another I assume the Southerners have cracked the issue with Identity contamination as I find it highly unlikely that they have so many heat medallions to supply whole air ships without Compounding being an option - same with Connection.

43 minutes ago, Isilel said:

IIRC we don't actually know if Allomancers burning unkeyed storages would get the 8x(?) amplification of the attribute stored that natural Compounders get or just the same amount as stored, delivered at the rate of burning speed of a given metal. IMHO, the latter is more likely, since the former would be too overpowered.

Keep in mind that without the ability to store the attribute, it would be substantially harder for the Allomancer to regulate the burst of Feruchemical attribute. Using Gold in this trick obviously would be useful - but then Augurs aren't known for the utility anyway. Huge bursts of weight or heat could get you or people around you killed if used unwisely. Considering that at present Hemalurgy is required to make it work, I wouldn't put it as more powerful than A-Duralumin enhancement which currently also needs Hemalurgy. Also, this WoB:

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Kurkistan

Could an Augur Compound Health out of a goldmind if its proper owner messed with Identity in the right way?

Brandon Sanderson

This is possible

General Signed Books 2014 (Jan. 22, 2014)

 

[Isilel]

@Duxredux:

Annotation to the chapter 3 of  "Hero of Ages" doesn't make any distinction between how TLR learned to compound and how the Inquisitors could have, given time:

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Mixing Feruchemy and Allomancy is what made the Lord Ruler so formidable. Fortunately, it took him a long time to figure out how to mix the powers correctly, and the Inquisitors haven’t had the time to practice.

Could have been superceded, of course, but a quick search of Arcanum didn't show me anything definitive.

Also, the timeline for Kelsier and Spook to get the former a body _and_ figure out and  set up medallion production in the South is tight enough without throwing additional stumbling blocks in their way.

It makes sense if people who survived Catacendre, whose souls had been warped by Ruin more strongly, could get more out of hemalurgy, including (easier?) access to hemalurgic Compounding, than subsequent generations. YMMV.

If burning unkeyed metalminds results in an 8x output of twinborn Compounding, then it would provide a completely trivial workaround for the identity contamination block on hemalurgic Compounding. It would just require 2 spikes instead of one - the first being for F-Aluminium, the other for the respective metal, to make a Misting/Ferring into an equal of a natural twinborn Compounder. It would be difficult for me to believe that the Set didn't think to try this.

Concerning mistings burning unkeyed storages, wouldn't speed of output depend on how quickly a given metal burns? And whether feruchemical storages burn at the same speed as uncharged metal? There would be far less flexibility than with feruchemical tapping, but it could be regulated by dosage of the metal, flaring and length of the burn.

Edited June 3, 2025 by Isilel

[Duxredux he/him]

Sigh. This is what I get for not quoting my sources. The following WoBs are where I got my understanding of the mechanics of Compounding and why I see no differentiation for multiplication in power output based on a random Allomancer burning an Unkeyed Metalmind, a natural Compounder like Miles or a Hemalurgist that has figured out a workaround for Identity contamination, as I assume the "charged yourself" caveat is Identity related.

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Andrew The Great (paraphrased)

What would happen if a person were to burn a metal that was Feruchemically charged using Allomancy?

Brandon Sanderson (paraphrased)

The metal used in Allomancy is like a key or a doorway to the power that Allomancy actually uses. The metal acts as a filter, much as the Aons in Elantris do, to determine what the power actually does. However, if the metal is Feruchemically charged, then it will basically become a super-burst of Feruchemical power with no Allomantic effect. The Feruchemical charge acts as a filter as well as the metal, and changes what the power does. in this case, say you were burning steel, you would just be massively speedy for a second, and wouldn't actually have the ability to push on anything Allomantically. Hope that answered the question. I get the concept, so if you need me to explain it differently, let me know and I'll try. Oh, the other thing I forgot is that this concept only works if it's a metal that you charged yourself. If it's a metal someone else charged, it would just work like regular Allomancy, and the Feruchemical charge would just cease to exist.

Andrew The Great (paraphrased)

If someone aluminum or duralumin burned the Feruchemically charged metals, what would happen?

Brandon Sanderson (paraphrased)

Basically the same thing as above, except with aluminum. Aluminum, they would just go away.

Idaho Falls Signing (June 20, 2009)

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Lyndsey Luther

Ok, last question. It was really difficult coming up with three questions that haven’t been asked already...

Brandon Sanderson

OK... you’re not going to ask me the “what would you ask me” question?

Lyndsey Luther

Not quite...

Brandon Sanderson

OK good, because I hate that one! (laughs)

Lyndsey Luther

My question is if there’s anything that you’ve never been asked that you would like to talk about?

Brandon Sanderson

Oooooh, ok. Hm. That one is so hard! Every time people ask me something like this... What have I never been asked that people should be asking, is basically what the question is? Something that the fans have just missed... They pick up on so much, that it’s hard... I do wonder if, you know… all the magic systems [in my books] are connected and work on some basic fundamental principles, and a lot of people haven’t been asking questions about this. One thing I did get a question on today, and I’ll just talk about this one... they didn’t ask the right question, but I nudged them the right way, is understanding that tie between AonDor [the magic system from Elantris] and Allomancy [Mistborn’s magic system].

People ask about getting the power from metals and things, but that’s not actually how it works. The power’s not coming from metal. I talked a little about this before, but you are drawing power from some source, and the metal is actually just a gateway. It’s actually the molecular structure of the metal… what’s going on there, the pattern, the resonance of that metal works in the same way as an Aon does in Elantris. It filters the power. So it is just a sign of “this is what power this energy is going to be shaped into and give you.” When you understand that, Compounding [in Alloy of Law] makes much more sense.

Compounding is where you are able to kind of draw in more power than you should with Feruchemy. What’s going on there is you’re actually charging a piece of metal, and then you are burning that metal as a Feruchemical charge. What is happening is that the Feruchemical charge overwrites the Allomantic charge, and so you actually fuel Feruchemy with Allomancy, is what you are doing. Then if you just get out another piece of metal and store it in, since you’re not drawing the power from yourself, you’re cheating the system, you’re short-circuiting the system a little bit. So you can actually use the power that usually fuels Allomancy, to fuel Feruchemy, which you can then store in a metalmind, and basically build up these huge reservoirs of it. So what’s going on there is… imagine there’s like, an imprint, a wavelength, so to speak. A beat for an Allomantic thing, that when you burn a metal, it says “ok, this is what power we give.” When it’s got that charge, it changes that beat and says, “now we get this power.” And you access a set of Feruchemical power. That’s why Compounding is so powerful.

Open The Fridge Interview (Nov. 16, 2011)

The actual mechanism for Compounding doesn't care if the storage belongs to you, it works anyway - whether or not you can access that attribute has to do with Identity. This is why Vin could burn one of Sazed's metalminds and see a hazy power reserve but not access it which Sazed confirms is what it looks like when a Feruchemist tries to access another Feruchemist's Metalmind. 

 

As for specifically if a random Allomancer can Compound with the an Unkeyed Metalmind, this WoB. Again.

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Kurkistan

Could an Augur Compound Health out of a goldmind if its proper owner messed with Identity in the right way?

Brandon Sanderson

This is possible

General Signed Books 2014 (Jan. 22, 2014)

 

On 6/2/2025 at 10:33 AM, Isilel said:

Annotation to the chapter 3 of  "Hero of Ages" doesn't make any distinction between how TLR learned to compound and how the Inquisitors could have, given time:

Quote

Mixing Feruchemy and Allomancy is what made the Lord Ruler so formidable. Fortunately, it took him a long time to figure out how to mix the powers correctly, and the Inquisitors haven’t had the time to practice.

Could have been superceded, of course, but a quick search of Arcanum didn't show me anything definitive.

Also, the timeline for Kelsier and Spook to get the former a body _and_ figure out and  set up medallion production in the South is tight enough without throwing additional stumbling blocks in their way.

It makes sense if people who survived Catacendre, whose souls had been warped by Ruin more strongly, could get more out of hemalurgy, including (easier?) access to hemalurgic Compounding, than subsequent generations. YMMV.

I feel like I'm missing the main idea you're trying to convey here. Could you give a more explicit description of the state of the Compounder you're visualizing and the difference between them and Era 2 Compounding?

I also don't get why Kel's technological advancement timetable would have more stumbling blocks if they had to deal with Identity contamination for Compounding. They had to address Identity in order to make Feruchemical Heat stores that could be tapped by any Southerner, right? 

If the idea is that Kel simply had to hightail it down to the South to make sure they could Compound with the strained Era 1 soul, ignoring the Identity of the distributed stores for now, my issue with this is that I assume that whatever solution Kel cooked up to establish the Firemothers and Firefathers has to still work for the modern Southeners who would have the same issues with Hemalurgic Compounding as the North. If the Firemothers and Firefathers are Hemalurgists who somehow can Compound to create Heat stores to sustain the entire population, they would have to rotate them out as they get old and die. No way are they outliving Marsh and his bag of Atium. If the Era 1 weakened soul was a major factor, at some point future generations would fail to produce viable Firemothers and Firefathers.

On 6/2/2025 at 10:33 AM, Isilel said:

If burning unkeyed metalminds results in an 8x output of twinborn Compounding, then it would provide a completely trivial workaround for the identity contamination block on hemalurgic Compounding. It would just require 2 spikes instead of one - the first being for F-Aluminium, the other for the respective metal, to make a Misting/Ferring into an equal of a natural twinborn Compounder. It would be difficult for me to believe that the Set didn't think to try this.

Passing over the part about the Compounding multiplier, I could believe it. Keep in mind that it was the Terris Enclave that were secretly exploring the nature of the Spiritual Feruchemical attributes. I could believe the Kandra found out that line of research but that perhaps the Set hadn't extracted that information from them yet. The Kandra are considered Marsh's brethren, so he may also be giving them more information than the Set has by the time of VenDell's discussion with Wax and friends.

It could also be the Set never identified a Trueself Ferring to target or harvest. A Terris wearing an Aluminum ring or band would never be identified by a Set Lurcher or Coinshot looking for Metalborn with rings, bracers, metal vials or dust pouches to kidnap or harvest from since the Aluminum would never be detected. A Trueself Ferring wouldn't take a job utilizing their powers or have visible indicators like variable weight, speed, intermittent glasses (for F-Tin), or muscle mass either. Considering how hideously expensive Aluminum was, a Trueself Ferring might not ever touch pure Aluminum or blatantly carry a small fortune on their person. Add in Terris secrecy with their research and finding a Trueself Ferring is definitely non-trivial.

It's also indicated repeatedly that the Set aren't as focused on Feruchemy as they are Allomancy and they aren't very familar with utilizing it properly. Kelesina was shot while wearing an unkeyed Goldmind full enough for Wayne to survive a small army shooting him for crying out loud. She just lay there while the Terriswoman took the bracer and then shot her again. The showdown between Wax and Edwarn in TLM pivots on Edwarn forgetting Wax is a Feruchemist. At the beginning of TLM, Marasi notes that the Cycle who became a Brute Ferring was very unpracticed with his powers despite the expanding suit. It looks like they use Feruchemy when it's convenient and available, but their R&D was researching Malwish airships & tech, non-lethal Hemalurgy, and Allomantic Eugenics - though it is true Telsin shows off the breakthrough in F-Tin allowing pain storage. What's obvious to us may not be obvious to them even if they had found a Trueself Ferring for experimentation.

On 6/2/2025 at 10:33 AM, Isilel said:

Concerning mistings burning unkeyed storages, wouldn't speed of output depend on how quickly a given metal burns? And whether feruchemical storages burn at the same speed as uncharged metal? There would be far less flexibility than with feruchemical tapping, but it could be regulated by dosage of the metal, flaring and length of the burn.

Mmmmmaybe. That might work for some attributes, I'll grant you that.

I had to dig around to figure out why my reflexive assumption was that it would be potentially dangerous without a way to store the attribute and use it like a regular storage. I identified three factors, though I'm open to interpretation - WoBs below if you want to read them yourself and come to your own conclusion. First, it's actually really hard to go below a standard burn in Allomancy. Going up to a flare is easy, but not down below the standard burn. Second, the amount of metals that Allomancers use is tiny - shavings or powder even for the fast burning powers like Pewter so a little goes a long way - there's only so much you can limit the dosage. Last is the mutliplicative nature of Compounding (the number thrown out by Wax and Sazed is tenfold) - if you have a 10% store does that result in 100% rate of attribute "withdraw" when burning, cutting out the low end entirely?  In combination, we get bursts of power multiplied over the original storage even from tiny samples from Allomancers that generally can't do low level burns. I might have overstated the risk, but I think it's there - particular if it's an Allomancer who hasn't had the opportunity to practice like a normal Ferring would.

Spoiler

Seonid

Is the level of burning a continuous distribution, can I burn 0.1 level of steel all the way up to flaring? Or is it just I burn or I flare?

Brandon Sanderson

The more skilled you are, the more you have the ability to moderate that. For most people it is burn or flare. But you can kind of burn up to a flare, does that make sense? Going below is really hard.

Seonid

Can you push a flare?

Brandon Sanderson

Yes.

Salt Lake City Comic-Con 2014 (Sept. 4, 2014)

Spoiler

Brandon Sanderson

The longest lasting of the Allomantic metals is actually copper, which is used by Smokers to hide Allomancy. Tin is second, however. Steel and Iron are actually rather quick, but since they're generally used in bursts, it's hard to notice. Both brass and zinc are medium, as is bronze. Pewter burns the fastest of the basic eight, though atium and gold both burn faster than it does.

In my mind, it's related to how much 'work' the metal has to do. That's why pewter, steel, and iron burn so quickly. A lot of weight and power is getting thrown around, while copper only has to do something simple. However, I never really set any of these things hard-fast.

And, only atium is really all that rare. Because of the value of the metals, the noble houses expended a lot of resources finding and exploiting mines to produce the metals. This resulted in a slightly higher value for most of them as opposed to our world, but not really noticeably so, because Allomancers really don't need that much metal. Even fast burning metals, like pewter, are generally only swallowed in very small amounts. (i.e. A small bit goes a long way.)

TWG Posts (July 31, 2006)

Spoiler

Questioner

When either Rashek or a Twinborn like Miles, how does he fuel his metalminds? Does he have to actually burn the gold in order to fuel them? Because, I feel like there's a paragraph in here where you kind of explained it, but I feel like you didn't actually say that you had to burn more gold in order to fill a metalmind. Is that how that works?

Brandon Sanderson

Yes. You can cross the streams and use one to power the other. But you are using the metal to power your Feruchemy instead of your own-- You're using, basically, the power that's coming through the metal...

Questioner

So you do have to be burning one the whole time? Sounds good, good to know. So you could just infinitely fill it, basically? As you burn, you just use it to fill it and it just gets-- and that's where that comes from?

Brandon Sanderson

Yep. You are burning a metalmind that you've already filled, right? That's the key there. You fill a metalmind, then you burn that, and what that does is it keys the metalmind to the Feruchemy instead. Which normally no one can do because you could-

Questioner

You can't do both.

Brandon Sanderson

Yeah. But if you can do both, you fill a metalmind, you burn that metalmind. What comes out of it is Feruchemical power instead, and you then are filling the metalmind with more.

So Allomancy is fueled by the power of the Shard. So what you're doing is you're powering your Feruchemy with the power of the Shard, instead of your own body. Using their Investiture instead of yours. Which is very dangerous.

Idaho Falls signing (Dec. 29, 2018)

 

 

Last side note, that HoA Annotation you referenced was addressed below. Apparently he was trying to get at the concept of intent and hadn't really refined it yet - he doesn't address what this has to do with what it says about Compounding. 

Spoiler

Moogle

Compounding requires practice, according to The Hero of Age's annotations. And yet, it's apparently as easy as burning a metalmind. What was going on that meant the Inquisitors couldn't figure out how to do it (despite Ruin likely knowing how and undoubtedly wanting them to learn) for over a year? What skill did they need to practice doing, exactly?

And what happened while they were practicing burning metalminds without successfully Compounding? Did they get an Allomantic effect?

Brandon Sanderson

What I think I was getting at in the annotations was a cosmere magic rule that, perhaps, I hadn't completely refined yet. This is the idea that INTENTION is vitally important to the workings of most cosmere magics.

You can learn to burn metals instinctively over time, but it does take time--time for your body to figure out what it's doing. If you have instruction and guidance, you can pick it up in an evening, like Vin did. Same goes for most of the magics. This ties into Awakening, with the idea that you have to form a command.

During Warbreaker was where I really refined this aspect of the magic. Logically, since the beginning of the cosmere, I've wanted all three Realms to be important to the way the magics worked. The "Practice" therefore for compounding is mental practice--a barrier to overcome in understanding what is happening, and what it will do to you.

If you already know all of these things by having it explained to you, that barrier is far less high. I think that was what I was talking about in the Annotations, without really having the idea specified yet--though I'd have to look back at the annotation and re-read it to say for certain.

Worldbuilders AMA (Dec. 3, 2015)

Don't get me wrong, I'm fine if I'm wrong and need to update my understanding, I just don't have a clear enough understanding of what you're trying to convey.

Edited June 4, 2025 by Duxredux
Clarity and additional thoughts.