Chapter 122 gave us many answers about the SnK universe (creation of the 9 powers, how Ymir obtained her powers), however there are still unanswered questions. One of them is in my title : how were the pure Titans created.
On other threads, it has been evocated that 9 Titans is the maximum number of Power that exist. We can't divide the Power again like it happened with Ymir's death. It's impossible that in 2000 years of history, no one tried to divide the powers again. And, as we can see, there are still 9 Powers, which mean none of the attempts has worked.
BUT. What if, when they understood that they couldn't create more Titans Power (I suppose it happened in the decades following Ymir's death), the holder of the Founding Titan used his/her power. When the Founding Titan is used, the holder meets Ymir in the Paths. What if he/she simply asked to get more Titan Powers. Ymir accomplished this wish, but it didn't end up exactly has the Founding Titan wanted : and here we have the first Pure Titans. By trying to create new Titans Power, which is impossible, we ended up with some SoY transformed into what we call the Pure Titans.
Even if my theory could be wrong, I really think the creation of the Pure Titan has something to do with the Founding Titan asking Ymir something in the Path. It's pretty logical, it's the place were the Titans are made.
I really hope we get more of an explanation about pure titans (even just titans in general) before the series is over. At the moment it seems the way pure titans work is purely for the convenience of the plot. Why are they mindless? Why are some of them not completely mindless? Why is there no human in the nape, yet the human is able to come back when they eat a titan shifter?
The Talking Titan that Ilse encountered provided more questions than answers and that's never really been addressed at all since. Why did it start ripping its own face apart and then kill her (without eating her) instead of answering her questions? Was it the titan's reasonable mind fighting against some primal instinct to eat people? Have they been 'programmed' to behave this way by the founder similar to the Fritz vow to renounce war? If so, why?
That titan presumably died offscreen when they wiped out all the titans inside the walls. Which is even more maddening if we never get a resolution to that mystery.
I think, the more fantastical a story is, the more different it's world is from ours, the less likely it's events will make sense under severe scrutiny.
Think of our world, now think of how much a small change can impact all our lives in it. A few years ago there was no Whatsapp, and now it's almost impossible to live a "normal" life without it. Now, imagine if someone discovered teleportation, how much just that one power would change our lives? It's safe to say no one would be able to predict just how different the world would become, how many different applications there would be for this new technology.
In SNK, the world is very different from ours, and what's worse is that the rules keep changing as new chapters introduce new powers. If we did live in that world, I'm sure we would find a million different uses for every fantastical element in it. The author tries to imagine what that world would be like based on the rules he himself created. As he introduces new powers and changes the rules, he's at risk of undermining the logic of the world he created.
In a story like this, you have to take it with a grain of salt. Not everything will be able to be explained using the physics and logic of our world. It's good when the author is able to explain things in a satisfying way, but for somethings you just have to accept "it is what it is" or "it's Magic!". The fantastical elements will never be able to be fully explained, so they just have to be explained in a way that makes enough sense to satisfy most people.
It bothers me that ,almost at the end of the story, Eren comes in direct contact with Ymir and attains a "brand new bag" of powers, never seen before in the world. At this late in the game, the rules of what can be done and what can't be done should have been clear. If Eren is suddenly able to fix the biggest conflicts of the story with "Magic", it will be very disappointing.
You know, it's not because you don't like the Path Realm and that you're not making any efforts in trying to understand it that it doesn't make sense or whatever, or that it is pointless to try to imagine a few things that haven't been explained yet.
I am making theories based on the Path Realm because certain things haven't been explained yet (ex : creation of the Pure Titans, the possible automatism of certain parts of the paths). How is it an issue to make suppositions based on the datas we already have ? Just because it is a «magic world», we should stop making theories ? «In a story like this, not everything will be explained by using logic and physics of our world» Well, that's good, because I never used physics and logic of our world to make my theories. My theories are based on the paths, an element from the SnK's universe.
And basically, Eren asked for the Great Rumbling to be done. How is that an element that has never been introduced before ? They've been talking about it for a loooooong time. «If Eren is able to fix the biggest conflicts of the story with «magic», it will be very disappointing». As far as we know, Eren is going to use Titans to make an end to their problems (aka the world trying to eliminate them). This story is named «Attack on Titans», it has been about Titans since the beginning, how is that a problem that Eren uses Titans to fix de conflicts of the story ? If the «magic» is an issue for you, then why did you even started the story ? The only «brand new bag of powers» that is eventually a bith weird is the way Eren survives the beheading. But the rest, there's nothing new (eventually the message sent to everyone, but the FT can change the memories and a small part of the DNA of the SoY, so just sending a message to all of them isn't a problem).
I liked Brother Spider-man's idea of the first Pure Titans being created from failed attempts to divide/transfer the Titan Shifters powers. Maybe they tried to feed one of Ymir's daughters dead body to more than 3 descendents, or even non descendent humans, and only 3 of those descendents inherited some of her shifting powers, the others turned into pure titans, and maybe nothing happened to the non-descendents.
I'm sorry, maybe I wasn't clear before, I don't think having magic in these fantasy worlds is a problem. My problem is with inconsistent magic. In the DC Universe, the Flash can move with SUUUPER Speed, and that's fine, because it's a rule we already know and accept as a fact in that world. Now, if out of the blue the Flash starts to shoot laser beams from his hands, that would be "magic" in that world, something that would break the rules as we knew.
Eren using the Rumbling is fine, as you've said, we knew about that power for some time. The problem is his new form. We can assume he will probably have some amazing new powers to go with the new look. For some time, the world knew about the 9 Titans and even their respective powers (more or less). Maybe previous Founding Titan Kings have used its powers in amazing different ways in recorded history, like the creation of the Walls, unfortunately we, the readers, don't know much else. Eren now yields power closer to Ymir than anyone else we know of, and since Ymir has died 2000 ago, to the point the world doesn't even remember if she was real or not, there is no way of knowing what her powers were, nor what Eren can do now. Right now, the author has given Eren a "magic" card, he could manifest any supernatural power that is convenient to him, or the story, but I just hope he doesn't. This sort of sloppy world building bothers me.
Since Zeke said the Founding Titan could ask Ymir to change the physiology of all eldians, it's imaginable that Eren could ask Ymir to remove the "Curse of Ymir" and turn all eldians into "just humans". But, if Eren can indeed do this, I would be very disappointed, because that would mean King Karl Fritz was an idiot for not doing this before, and also because it becomes one of those "magical solutions" to the main problems of the story I was talking about.
Look, I think the author put a lot of effort into creating a story with some interesting characters, conflicting moral dilemmas, foreshadow, references that tie the narrative to north mythology and WWII, and even attempted to make a very elaborate stable time loop. So, for all of that, I'm willing to overlook some of the plot holes, inconsistencies and new powers/rules that were introduced along the way.
P.S.: A theory about the Paths Realm - The Founding Titan is connected to all eldians through the paths, since we saw he was able to speak to all of them at once. He can also change the memories of all of them, as it's been told several times. We also know the memories of those who are already dead are accessible through the paths, though we don't know exactly "where" those memories are stored, inside that hosts body/mind or are part of the Paths itself, or maybe all in that central pilar, "Yggdrasil's" trunk, aka the Founding Titan. Right now, Eren could use his infinite time in the paths to visit all the memories of all the eldians in the world, and as such all these memories would become part of his memories, therefore, if the previous Founding Titans have also used that infinite time to see the memories of all eldians alive in previous times, it's possible that the memories of all the SoY that have ever existed are all there, still accessible by the Founding Titan.