There were a couple of threads lost regarding entities shifting realms, which started with my question about a faerie whose story became that of a truly venerated saint. I'm going to post a short recap of some of what we concluded- we won't be able to reconstruct the entire conversation, but it opens the topic back up for discussion:
faerie->divine this can occur by the will of God, there are possible historical examples of pagan deities "becoming" saints, I would add that any other mechanism by which a faerie might become divine would probably have the caveat "by the will of God" appended to it
infernal-> magic there are examples in canon, but these come with the caveat that the magical entity may be under the delusion that it was once infernal
infernal->divine the top idea is that if something infernal created an identity close enough to divine (in order to lead people astray) to be of issue then God would probably create the requisit saint/angel/entity whole cloth. I would posit that a faerie emulating the infernal role and bringing it closer to the divine is a likely hidden step much of the time
anything->faerie there are cases where mortals can become faerie, and it is posited that the old (magical) gods became the first faeries, at the same time anything becoming faerie could simply be a faerie imitating their story.
faerie->infernal this seems possible if the faerie's story becomes sufficiently corrupt, though whether it would become an actual demon instead of simply a corrupted faerie is suspect
divine->infernal historically there is the fall, and presumably divine beings are still capable of falling, but this would have to be done by free will
magic-> infernal certainly there is corrupted magic, and indications (djinn and dragons) that this has happened, though again it is unlikely they became full fledged demons.
magic->divine not discussed in depth but "by the will of God" seems to cover everything
faerie-> magic I don't recall discussion or example of this happening. Not sure what would push a faerie in this direction since having a story which defines it as magical has proved wholly inadequate. Perhaps if they stay in the same story for multiple Millenia?
The faerie are so alien, it's hard to say if they were capable of corruption in the conventional game-sense of the term. But considering they aren't divine, corruption is definitely possible. in the RAW werewolves and vampires are Fae, it begs the question of how that could stand and not be infernal, unless infernal is more than just evil.
vampires and werewolves exist (5th ed) as faerie, magical, and infernal models.
and in terms of corruption their stories can certainly take an infernal bent and RAW clearly suggests they would become infernal.
I could see a fallen angel, who works hard to redeem themselves is still cast out (not human so grace is not handed out freely for the asking) but isn't infernal any longer, and since their nature is one of truth at that point, one would think it was a Magic creature (who mourns their fall and regrets their rebellion). Or isn't infernal but still thinks mankind is unworthy hence the no grace. Could be a powerful adversary, or ally depending upon the circumstances.
I am not aware of any (in historical literature) demon that was redeemed by the divine. I could see that a faerie might take on the story and play act it, but I'd think that's as far as it goes. The fae story might be the emotional moment when a fallen demon is forgiven in an ultimate act of ineffable grace. But aside from the play acting of this story, I wouldn't see it making the faerie any closer to divine.
Huh, given the corpus of works, I wasn't aware of the infernal werewolves and vampires, I just reeled form the shock of ... fae?! really?! I will have to look again - do you know where I could look, the stack of books is intimidatingly high!
I didn't claim that infernal to divine was historical. In the vanished thread it was raised as a hypothetical and this was the conclusion which was reached. Obviously infernal influences would not be a part of any historical record, aside from real world religions which AM decided to list as infernal cults which seems to be a regretted decision at thispoint.
I believe they have been mentioned in either against the dark or ROP:I. I didn't especially note where something which seemed obvious was noted- anyone who sells their soul and becomes a vampire or werewolf would inherently be infernal, also there can be an infernal curse bestowing these conditions. I believe the core book specifies that the lycanthrope flaw can be infernal in origin.
though while we are on the topic of infernal-> divine I suspect non-demonic infernals (an infernal ghost for example) could be saved and converted...