If you finally bowed to the pressure and decided to give Alchemy of Souls a chance, there’s a possibility you’re a little confused about how everything works, so here’s a very short primer on it.

This technique was developed by a very popular and talented mage of Daeho and years later, Jang Kang, Jang Uk’s father, started learning it.

From what we learned throughout the series, and in the first few episodes, he had started using the technique to help people who had lost their loved ones – he would then shift the souls into dead bodies. 

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But he soon started to see the error of his ways when the people he had helped would turn into strange beings whenever they weren’t fed human souls. He didn’t plan for the technique to have a monthly subscription, but that’s what he got, and everyone he had helped would start turning eventually. So he and his other mages were then tasked with vanquishing whoever had done it before they killed people.

The way the Alchemy of Souls works is that there will be two bodies and two souls, and essentially, the souls are swapped. So person A’s soul goes into person B’s body and vice versa.

It’s very handy for a person who is trying to avoid detection in a crowd or escape from people who are trying to harm them, which is exactly what Naksu does eventually. But then she gets stuck in a weak girl’s body (Mu Deok), and I’m sure we all know how that panned out.

Now, a person who has undergone the Alchemy of Souls procedure (called a Soul Shifter) usually has a blue mark somewhere on their body. Up until Naksu, the blue mark was usually somewhere very visible and easily spotted, but hers was in her eyes, and that is how she was able to escape detection for a very long time.

If you remember what I said earlier about swapped individuals still needing sustenance in the form of human souls, then you might be wondering how come Naksu never had to feed off the energy of another human being. And that is a whole other thing, but basically, she is a vessel.

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Imagine a person has undergone the procedure twice; they build up a type of resistance to whatever side effects of that procedure, and that was exactly what happened in Naksu’s case.

When she mistakenly entered the body of this girl, she wasn’t aware that this girl had also undergone the Alchemy of Souls procedure when she was still a baby in the womb, so that is why she never shrivelled or suddenly started needing human souls.

This need for human souls is oftentimes uncontrollable, and if a Soul Shifter doesn’t get the sustenance, they petrify (turn into stone) after being killed. 

And if you’re curious to know how long a person could live if they carry out the Alchemy of Souls, I would say they could very well carry out the procedure several times and end up living forever.

Look at it this way: if an old man carries out the Alchemy of souls and enters into the body of a 10-year-old child, he gets to live the natural life of that child, and if when he feels that is near, he carries out another procedure and goes into the body of another 10-year-old child, he will live that long again, and the process repeats itself over and over again, so basically, he could end up living for thousands of years.

Of course, I see no reason why anyone would want to do this, but then again, different people, different flavours, and different wants and needs. So for some who feel that it’s paramount that they remain on the earth for that amount of time, this might be the procedure to go with.

The thing about the Alchemy of Souls is that most people who carry out these processes do it for very nefarious or very unseemly reasons. For example, Jang Kang realized that the very procedure he was using was the one that would ruin him when he swapped souls with the king and ended up setting the stage for a potential conflict.

If you’ve watched this series, then you probably know that the king swapped souls with him in order to bear an heir, which he did with Jang Kang’s wife, and he was so disgusted at himself and angry at the world, so he sealed his son’s energy path so that he would never be threatened by the actual prince.

To find a Soul Shifter, you generally had to wait until they manifested (and they would). But, the Jin family of Daeho who maintain all the powerful and magical relics of Daeho would often come up with different items that could sniff them out – like the Gwigu. 

So while the Alchemy of Souls was a procedure that everyone collectively agreed to fight against and shun, there’s no limit to human greed, and finding out that there’s a way you can leave your body and enter the body of your choice is a game-changer that even the most principled person will probably not be able to resist, and this happened over and over again in Alchemy of Souls.

Finally, the Alchemy Of Souls is definitely not a real process, but a girl can dream. 

So what do you think? Imagine you meet a mage today who tells you he can perform the Alchemy of Souls, would you take his offer? Let me know in the comment section below.

And I saw an edit of Alchemy of Souls that absolutely brought on my brain rot for the 1,567th time, so the related posts have more theories and short essays about other stuff related to Alchemy of Souls.