So, Brian Chen asked me an excellent question: “Doesn’t the scorpion kill by forcibly dragging the victim’s soul across the Sanzu River in the afterlife? How did Bai Ning manage to capture its soul and refine it into an artifact spirit?”
And while answering it, I realized it might be worth sharing the explanation with everyone.
Fair warning: none of this is something you need to know to follow the story. This is very much me indulging in a bit of worldbuilding nerdery; feel free to skip it unless you’re in the mood for that sort of thing.
So, without further ado, here’s the answer:
To make sense of the Netherworld Scorpion’s death sting, there are really two things we need to keep in mind: how souls work in this setting, and how the scorpion actually interacts with them.
For the first, a very important thing to understand (and this has not really come up in the story yet, and likely will not in much detail) is that souls in xianxia, and in the actual Taoist/Buddhist syncretic traditions that inspired it, are made up of… other souls. Or, to put it in a way that is slightly less confusing, they are not a single unified piece so much as they are composed of multiple aspects or layers. Kind of like how the body has organs, bones, muscles, and so on, the soul too is comprised of subcomponents, or what we can reasonably refer to as parts of a soul.
More specifically, a soul is comprised of hun souls and po souls*. Po souls are, broadly speaking, the aspects that govern the functions of the body. You can think of them as being responsible for systems: digestion, respiration, reflexes, and so on. The hun souls, on the other hand, are both more abstract and more relevant here, because they govern three increasingly hierarchical aspects tied to the spiritual: life, sentience, and sapience.
In other words, one hun soul represents the fact that a being is alive at all (something shared by humans, animals, and even plants), the second represents sentience (the capacity to feel and perceive, which animals certainly possess), and the third represents sapience (not just feeling, but thinking, reasoning, and articulating).
So, a plant’s soul might have one hun soul and a handful of po souls, depending on how complex it is structurally. An animal can have up to nine souls total, typically two hun and seven po, though often fewer. Humans, or more broadly any being capable of higher reasoning, can have up to ten, which is the natural maximum.
Now, there are exceptions and caveats to all of this, but in a general sense, that is the framework.
So, is this exactly how it works in the story? Broadly speaking, yes, but in practice it affects things far less than you might expect. When I was designing the reincarnation system, having this ten-part soul structure was important for a number of reasons, one of which was that I needed a “true” or “sacred” aspect of the soul that could persist as the self and undergo reincarnation.
At the same time, this is still a xianxia setting, so all the familiar elements are there: grandpas trapped in rings, demons sealed in jars, spirits used as fuel, artifact spirits, all of that.
There’s always a bit of a balancing act, though. These mechanics are interesting at a design level, but that doesn’t necessarily mean they need to be front and center in the narrative. If anything, going too deep into it risks cluttering things and making the story harder to follow when the core ideas are already doing a lot of work. So I made a conscious choice not to emphasize it too much.
The hun and po framework exists in the setting, but its impact on everyday understanding is minimal. Most people simply refer to the soul as the soul, much in the same way that qi has more specific classifications (natural qi in the world being called jing, for one) but is still just called qi in common usage. It is something people might learn in a scholarly context and then promptly ignore because it rarely matters in practice.
That said, it does have very specific implications where it does matter.
When people talk about capturing someone’s soul, they are almost always referring to the sapience hun. When Song Shaoyue captured Ming Changge’s soul, that was the aspect she sealed and tortured. When someone is killed to create something like a False Core Pill, the entire soul is consumed, but the destruction of the hun, especially the sapience aspect, is what makes the act particularly horrific.
And when a human/humanoid** dies, it is specifically the sapience hun, referred to as the Bright Spirit, that enters the cycle of reincarnation. What happens to the rest of the soul, whether other hun aspects or the po souls, is that they disperse. The exact behavior depends on the type of being, but for humans and humanoid entities, the process is almost immediate once the Bright Spirit departs. So if a human/humanoid dies, their Bright Spirit moves on, and everything else dissipates. This is why you cannot simply kill someone and then extract their soul afterward. By that point, it is already gone. If someone wants to manipulate a human soul, they must do so before death.
This is not universally true for all beings. Spirit beasts, animals, and other entities can behave differently depending on a range of factors. When something like a spirit beast dies, its soul does not vanish immediately. Instead, it lingers for a short but meaningful window of time. This is not a long duration, and the underlying reason ties back to the idea that humans occupy a special place in the metaphysical hierarchy, which, to be clear, is not just a narrative choice but something drawn directly from the mythological traditions that inspired this system***.
During that window, even if the beast possessed higher intelligence and thus a sapience hun, the other hun and po components remain present and accessible.
So, to finally bring this back around, what Bai Ning captured, and what cultivators generally capture, is the second hun of a beast, the one associated with sentience. There are a couple of reasons for this. First, capturing the Bright Spirit is inefficient and often counterproductive. It is the thinking, self-aware aspect of the soul, and while cultivators may want companions, they typically want something they can shape, guide, and control (pets, basically). Second, removing the sentience hun does not fundamentally weaken the spirit; it simply makes it more tractable.
What Fan Mei captured when Bai Ning killed the Niumowang was this second hun, which we will refer to as the Dark Essence. What Bai Ning captured from the dragon was the same.
This is also a good point to briefly touch on dragons. Dragons are unusual in that they begin with nine souls and only develop the tenth over time. Early on, they operate at the level of animal intelligence, but as they grow and advance, particularly as they approach rank eight, they begin to solidify their final hun, the Bright Spirit, and become fully sapient. The lava dragon was in the middle of this transition, right on the cusp of that threshold, so the aspect that entered the Sanzu River and was affected by the Netherworld Scorpion was precisely that developing hun.
* Random aside 1: You might wonder, since the dantians and meridians are also part of the soul, how they fit into this framework. The easiest way to think about it is that they are shared structures across all the soul aspects. Imagine the souls as layers of fabric, and the meridians as the threads stitching those layers together. The classification of meridians is actually tied to how many layers they pass through. If they run through all ten, they are the eight primary meridians. If they connect two hun and all po, they are the twelve secondary ones. If they are limited mostly to the po and the most basic hun, they fall into the tertiary category, which I believe numbers around thirty-six, though I would need to double-check my notes on that. The dantian sits centrally within this system. This is also what makes the nascent soul stage such a big deal: at that point, cultivators start consolidating these multiple aspects into a single unified whole, using the nascent soul as a kind of base and gradually integrating everything into it.
** Random aside 2: Why do I keep saying human/humanoid? Well, it’s because in myth and culture, human souls are treated as central simply because humans are the ones constructing these systems. Within the story, however, there is also an in-world Watsonian justification. Across countless worlds, even those not originally inhabited by humans, intelligent life tends to converge on humanoid forms. That is because the human soul structure is particularly well-suited to cultivation, so evolution, adaptation, or even artificial shaping tends to move in that direction.
*** Random aside 3: If you have made it this far, you might reasonably ask whether humans can be turned into artifact spirits. The answer is yes, but it is rarely useful. If the Bright Spirit is used, then you are effectively binding a fully sapient being that will resist you at every turn. If the Dark Essence is used instead, you are left with something that lacks higher cognition and is correspondingly limited. There are techniques that use fragments or shades of human souls as puppets, but they never became widespread because they are inefficient compared to alternatives (or plain demonic, which is another matter entirely). Cases where a full human soul is bound do exist, but they tend to resemble accidents or unresolved remnants rather than deliberate design.
Recognize I’ve thrown a lot at you. Any questions? 😊