Quote Originally Posted by Veloran View Post
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And as you rightly pointed out, the Ancients are very (aetherically) dense. So if you're talking equivalent exchange, we're talking about an equivalently large-scale sacrifice of countless lives. And it's not hard to see why there would be opposition to that.

If you watched through the same lectures that you linked, you don't really have to have a rule-driven hard magic system in place to create a satisfying narrative. The Ancients' creation magic is very much a soft system. Concentrate on the form of the thing that you want to create, snap your fingers, and then there it is. You can solve pretty much any problem that you like with such a system in place. The limitation is the cost, which is what sets the victory condition. You can save your planet - but at the cost of half of the population of Amaurot. You can restore the destruction wrought by the Final Days - but at the cost of a quarter of the population of Amaurot.

Without that cost, you sidestep the conflict. If it was just a matter of saving up enough aether crystals or biological waste products to pay Zodiark, then there never was a conflict at all. You just snapped your fingers and solved the problem. If it was just merely a question of aether, why do you need to sacrifice lives at all? Get every Amaurotian to spare a snifter of their bounteous reserves. But we're not trading in aether. We're trading in souls. And that's why the price paid has meaning.

That's the same reason why time travel as a 'magic system' has to have a victory condition/constraints in place as well in order for it to be satisfying. If you can undo events at will, nothing has consequences, and there is no conflict. You just snap your fingers and undo the bad event. Elpis very deliberately teases you with this by setting the constraint before you enter and then toying with it as you travel through the area.