Mercurius
Legend
I haven't seen the quote, but maybe he meant "Tiamat can't die" because she's core to D&D canon. Sort of like saying, "mind flayers can't be totally eradicated from the D&D cosmos." I mean, technically they could be but...they're mind flayers! We need them
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Anyhow, it has never been clear what the nature of the gods is. I think that's where cultural interpretation comes in, and what the DM decides is true for their world. Like our world, each cultural tradition has their own explanation, and perhaps "the truth" is forever unknown to mortals. I think what ends up happening is a lot of folks fall back on an objectivist take, that there's a truth to "how things are," rather than the ultimate truth being unknowable and any "known truth" being particular to the individual and/or culture.
This points to why I'm hoping they include a "build your own cosmology" chapter in any Planes book. DMs would be encouraged to pick from several paths, or hybridize them as they so desire: Either the default/canonical cosmology (whatever that may be); a variant cosmology; or a build-your-own cosmology.

Anyhow, it has never been clear what the nature of the gods is. I think that's where cultural interpretation comes in, and what the DM decides is true for their world. Like our world, each cultural tradition has their own explanation, and perhaps "the truth" is forever unknown to mortals. I think what ends up happening is a lot of folks fall back on an objectivist take, that there's a truth to "how things are," rather than the ultimate truth being unknowable and any "known truth" being particular to the individual and/or culture.
This points to why I'm hoping they include a "build your own cosmology" chapter in any Planes book. DMs would be encouraged to pick from several paths, or hybridize them as they so desire: Either the default/canonical cosmology (whatever that may be); a variant cosmology; or a build-your-own cosmology.