Reynard
aka Ian Eller
And I'm saying that high level adventures do not need to have world shaking stakes. There are plenty of other stories you can tell with demigods. Greek myths and comic books should get you started on possibilities.This is a thread about designing challenges for high level parties.
My comment of ''15th level parties should be dealing with existential threats to the entire realm. These are people that can go toe to toe with primal Demon Lords and expect to win. Think planar travel, artifacts and similar things being features, with the fate of the world in the PCs hands.'' is entirely on point with that topic, and clearly within the scope of that topic.
When designing high level adventures, that's your starting point for where to begin. Think big.
That then lets you use antagonists, who are no fools, have dealt with high level PCs before, know all the tricks and abilities that high level PCs use, know effective counters, and know how to exploit the weakness of PCs. It lets you use alien or unusual environments, that force the PCs to think outside the box.
If your groups mission is 'Travel to the 88th layer of the Abyss, and slay Demogorgon (who is well versed in the abilities of high-level adventurers, with millennia of experience) before he destroys the Macguffin of Doom during the imminent Astral convergence and merges the Prime material with the Abyss' your party is not just plane shifting next to him, and nova striking him like a chump.
More importantly, this thread is specifically about finding design solutions to design problems. It is not about soft topics. Those might be interesting to discuss but I am trying to solve the technical issues with high level adventures, or at least determine definitively that they exist.