[Spoiler] Isn't Dark Knight using Akasa ?

[Lyth]

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The Mistborn analogy doesn't apply well here. The central problem is 'main villain is immortal, nobody can defeat him.' When the resolution to that conflict is 'The protagonist was secretly more powerful than she realized', then there never was a conflict to begin with. It doesn't really matter when you introduce that fact. Deus Ex Machina eliminates the central conflict by sidestepping it. Sanderson's point about having a 'victory condition' is important. He contrasts Helm's Deep and Pelennor Fields in that the solution to both problems is similar (big army shows up, we win), but one has a foreshadowed victory condition (survive for five days) and the other does not. Without that victory condition, there is no dramatic tension, because you can just win at any point that you feel like. You can, however, distract the audience from that condition, which is why its to your advantage to introduce the rules of the game earlier rather than later.

None of this really applies to Dynamis. I think if you want to see a better example of this principle, look at Ultima Thule. As you progress through the area, you're given some bits of information on how it works:
- Meteion can unmake people at will.
- Emotions govern the land, allowing a soul to stand up in defiance of Meteion even if she unmakes them. She has to break their spirit to win.
- You can use Azem's magic to summon your friends souls back at any point, but that resets your way forward. (this effectively sets the terms for the victory condition and hints at the solution - your 'friends' are more than the people that you're travelling with)
- When people return to the star, they regain the memories that they've lost.

All the pieces are on the table beforehand. The main conflict is an ideological one. Stand up to Meteion, and show her your will to live. If you wanted to discuss whether this setup works or not using the above framework, it would be relevant. Is it contrived? Anything can be if you choose to be critical enough. That's really up to individual interpretation. Maybe you liked it, maybe you didn't. I thought it was clever.

But as for the explanation of Dynamis that we get? I don't think that it has any impact on dramatic tension outside of pure symbolism. It's a world-building element. It's not the MacGuffin that solves the conflict. If you're going to blame anything, it should be Azem's soulstone.

When you have limited information to go on, you have to be careful not to infer more than you actually can. Aether interferes with Dynamis somehow. Does that mean that the two are incompatible? Meteion is still made up of Aether, even if it is a little thin, so they're not 'incompatible' per say. Is it that Dynamis transmits less effectively through Aether? Or is a better analogy to compare Electromagnatism and the Strong interaction, where the dominant effect depends on something like scale, causing one to 'drown out' the other? Can you use the two together, by say creating a box of Aether and opening it to stuff it full of Dynamis so that it can't escape? Break in case of emergency. What if the Flame in the Abyss refers to an interplay between Aether and Dynamis?

I don't think that Limit Breaks need to universally be one thing. In times of emotional duress, people can surpass their limitations. Perhaps some of these cases involve just Aether. Perhaps some involve just Dynamis. Perhaps they involve both. What we do know is that there are a lot of jobs out there that draw on forces that are not entirely aetherical in nature. Wrath, Darkside, and so on. Perhaps these have something to do with Dynamis. Perhaps there are other forces out there that we're not aware of. Either way, it adds a bit of nuance to our understanding of these things. Emotions are powerful in this universe.

I'm sure that we'll learn more as we go. For one, there is a lot about Void Magic and the Voidsent that we still yet don't know, and this is probably the one thing that I'm the most curious about. I wouldn't be surprised if we get a referential tie in here somewhere, especially given that Diabolos was the creator of Dynamis in FFXI. Second, as powerful as Amaurot was, it was isolationist, and it sounds like their contemporaries from 'across the pond' were quite technologically advanced as well. I doubt it was the center of the universe that its denizens made it out to be. I wouldn't be surprised if there was an 'Esthar City' lurking out there in the 'wastelands' of Meracydia or even in the New World. If Dynamis exists, there are surely people out there who have mastered its use, and yet others who would find our current powers to be underwhelming. There should always be room for growth, learning, and the promise of a journey to that next horizon.