I find it implausible because it doesn't state that. Too many times people try to shoehorn in their own interpretations when I feel like a statement should be taken at face value. If it said they are cast down into the Abyss, then fine that's what happens, but it doesn't so there is no reason to assume that these larvae are doing anything but squirming around in Kelemvor's domain. I'd say no new player who bought the SCAG to read up on FR lore would come to that conclusion but people who have been playing for a while will often fill in the gaps with prior knowledge.
If it was the case that they do get sent to the Abyss, I don't see any real difference between getting consigned to the Abyss and getting consigned to the wall, you're still getting horricially punished for not following a god, in fact the wall might be the better fate.
Two things.
1) I'm not shoehorning it in. I'm fully acknowleding it does not state that. But, much like I can assume "Wildfire's destroy eucalyptus trees" is a headline dealing with Australia, because that is the place where Eucalyptus trees grow, Soul Larva are seemingly exclusive to the Abyss. So, assuming they don't just spawn out of nowhere, and that all mortal souls go through his realm, and that all Soul Larva were mortal souls.... those are some clear logical lines.
2) You are not getting punished for not following a God. See, this is the difference. The people who got sent to the Wall could be simply insane, or ignorant. But, the souls in the Abyss are almost exclusively evil, and evil is a choice. You chose to commit evil acts, acts that drew your soul closer to the realm of Demons who are destruction incarnate.
Just like I feel little pity for the Lemure, who was a mortal who signed a contract with a Devil, I feel little pity for the Soul Larva, who chose their path of destruction and now reap that cost. And remember, they could still be claimed by the Gods, and there are some Evil gods in Faerun who could claim them.
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Amusing that people think that being turned into a wriggling lava to be enslaved and/or eaten by demons is "better" and less "problematic" than the Wall of the Faithless.
Doesn't sound much better to me. (It only happens to "bad guys" though, amirite?"
You put it in quotes, but yeah.
If you assume the alignment of the planes works, these Soul Larva would be nearly exclusively Chaotic Evil. People who believe in causing pain, wholesale slaughter, and death simply for their own amusement.
Meanwhile, the Wall applied to everyone who did not properly worship the gods, no matter the reason or even the length of time (see the former high priest of a goddess being made faithless like a month before his death and getting walled.)
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It seems like you are saying all gods in D&D are evil, to one degree or another, for allowing bad things to happen to good people. I suppose that is as valid as any other perspective.
How do you parse alignment being objective in this viewpoint? Ultimately corrupt to the core?
No, you misunderstand.
The Problem of Evil accepts three conditions.
God is All-Knowing
God if All-Powerful
God is Ultimately Benevolent
DnD gods are neither all powerful or all knowing. Good gods exist and they are opposed by evil gods. This makes sense. Evil exists, because good is not powerful enough to destroy it. But, the force of good do fight against the evils they know about.
The problem with the wall though is that every good diety in FR knows about it. No diety has ever been shown to be against it (except Kelemvor who reversed his decision because of terrible logic), and the Gods of Good allowed it to be created in the first place.
It is an evil they know about, that they can oppose and that they do not oppose. That is the problem.
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Yeah, it starts to break down when you consider a good character who (ignorantly) worships an evil power, or an evil character who worships a good power...
... every time I see things like this I remain convinced that Eberron has the best depiction of religion and faith in D&D.
Oh for sure, Eberron is amazing and there are always exceptions.
I don't see it as too likely though, since most of the evil deities in FR are... about as subtle as a nuke. You'd have to really stretch to find reasons for a good person to not realize that the god of "Kill everyone and bath in their blood" isn't a good guy.