That explanation doesn't really work in-setting. Inside the world of Faerun the causality would work the other way around; umberlee is evil and that's why the sea is treacherous.
I'm trained as a scientist, and one thing that teaches you - there is no such thing as "knowing" something, just varying levels of uncertainty.Perhaps that's what it means to some people, but that's not really the case. Faith is about believing despite the object of that faith being unproven. It's the difference between believing and knowing.
I would say just the opposite is true. The real world is packed full of things that exist "just because". Things that exist that are irrelevant to the PCs and the adventure are what give a world it's depth - the illusion that it exists independently. The Lord of the Rings (and the Hobbit, which mentions the fall of Gondolin) are chock full of references to things that are of no relevance and are not explained. That what makes Middle Earth feel so deep, when the fantasy worlds of other authors feel so shallow.
Because the author (Ed Greenwood?) Chose to make her evil. It matched his perception of the sea. All Art is subjective.
But FR has a plethora of gods - if you want to add another sea god with a different temperament there is no reason not to. In certain editions the rule for the FR was "all casters of divine spells must choose a god" but also "if you can't find one you like make one up".
Except real world pantheons and religions did have evil deities in their own pantheons and belief systems. They would not necessarily worship them, but they were still often part of the belief system. When you deal with absolute statements like this about real world beliefs operating in a certain way, you are bound to be contradicted. As I said - which you some how ignored - Yam was an evil Ugaritic deity who was regarded as evil by the Ugaritic people.
Empirical knowledge is uncommon, however it isn't nonexistent.I'm trained as a scientist, and one thing that teaches you - there is no such thing as "knowing" something, just varying levels of uncertainty.
Facebook status: "It's Complicated."Alright, but here (to tie this back to the OP) is the question. How many of those religions with explicitly evil Deities also had powerful demons that were threats to the gods that were not tied to those gods.
IMHO, it depends on the sort of stories that you want to tell/explore in your world.DnD though has both. We have Evil Gods, we have Demons, and we have the Devil. All three are existing simultaneously as foes of the gods of good. But do we need them to? Why have redundant aspects.
What the heck do the gods even do then? Are the Athar explicitly right?I do not think that is the general cosmology of the Forgotten Realms. Mystryl was the Weave of magic which fits that style but that was a specific case that seems to be an exception. Azuth is the god of spellcasters but he was mortal before that and there were spellcasters before him. When the gods were reduced to avatars during the Time of Troubles there were wild magic and dead magic zones which can be attributed to Mystra not being there to smooth out the Weave, and Bhaal did something with the life forces of assassins (its been a couple decades and I do not remember the specifics), but I don't remember a lot more happening in-world to the fundamentals of the world for the deific portfolio areas with the change in gods other than the change in AD&D editions from the out of world perception.
There are tons of ascended FR deities who became gods of things that existed beforehand. They seem to be champions of their domains, not determinants of them. There are interloper gods who come in and overlap with existing domains. I am not aware of descriptions of the fundamentals of the world changing when the Untheric and Mulhorandi pantheons entered the world. What I remember is the descriptions of their politics and their wars with orc pantheons.
It seems more like there are divine domains that individual gods can nonexclusively access and take from each other and lose or give to a disciple.
Alright, but here (to tie this back to the OP) is the question. How many of those religions with explicitly evil Deities also had powerful demons that were threats to the gods that were not tied to those gods.
Omitting any alignment from your collections of gawds would seem to me to imply some weird imbalance in the setting, and good gawds without evil gawds to oppose them seem purposeless from a storytelling perspective.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.