Speaking on the topic of repetitive topics... I've also had something that's kinda been... half-bugging me, half bugging that this gets said but -- as far as I've been able to tell -- never been gainsaid or questioned.
I've seen this brought up all the time without any real proof or backing behind it. It just gets... said a lot. Again and again. Accepted-as-fact by sheer repetition -- often across many Warhammer threads, because usually there's a lot of cross-pollination of posters in Warhammer threads, especially the more prolific fans.
But is there really actually all that much evidence behind the pop culture statement of "Gods are totally made fully out of belief"? Because as far as I'm aware, it's not actually really hard-said anywhere in texts. It is, at best, circumstantial evidence or inference -- done on the part of the readers.
And then repeated in every. single. Warhammer Fantasy thread I have ever been in.
As the time of a thread goes in, the certainty that somebody will state that gods are just bits of soul or don't have any real agency because of that or that gods are just the creations of human's beliefs and worship, approaches 1. ((Goodness knows that by this point, I basically don't question and bring up the whole 'Chaos feeds on all emotions' thing. Despite me vaguely thinking that it sounds like something that was the case in 40K, and people just backported to Fantasy, and then eventually just popularized it via repetition. It feels like a pointless battle to pick. Though even just... questioning the amount of certainty and evidence we have for this. And not just statements in a book, but... ... Gah. Sigh.))
((I remember another bit of lore interpretation, that was accepted-as-fact simply because it really felt true and because it got repeated a lot, that I myself thought was true until I came across some post in this thread, finally. And that was the Doom of Kavzar thing. Everybody talked about how it was the story of the people there getting turned into Skaven. People talked about how it was a meteor shower or 13th Bell that created the Skaven race there, and in one post about how it might have been an atemporal gambit by the Horned Rat; creating his race before he himself existed. And I'd even read the damn story myself and didn't think too deeply on it -- I guess I skimmed and overlooked things -- until some poster in this thread pointed out: "Hey, this story just has the Skaven show up?" And I gave it a second glance and went "Wait... yeah. That's true." And yeah, the story looks like the Skaven attacking the Dwarf underground town and also hitting the aboveground too. And also the town getting hit by all sorts of shit.))
And maybe there's some amount of dislike for what feels like a widely-too-popularized take on divinity in modern myth and pop culture that always goes "Gods need prayer to eat!" or "Gods are made up by human thought" because sometimes I'd wish it weren't the ground-based, go-to assumption that most stories or fanworks will default to.
Because I've seen some eyeroll-worthy ideas based on this human worship. Like a sincere argument that, hey, it's okay to sell guns to the Bretonnians because gods can be affected by belief and so if we just sell enough guns to the Bretonnians, they'll eventually change their worship and thus their goddess. (As opposed to something quasi-more-reasonable-ish like: "Well, maybe the society will change in a way that accepts some usage of guns. Such as in fixed defenses. Or as siege weapons. Or for peasants only. Doubtful, though -- but hey, it happened with the navy, right? So maybe...") ((That dates back to the really old quest by Gaius Marius. It also had some gems like an argument that, due to completed technical magical and soul stuff (which itself was questionable), Tomb Kings technically did not (or should not?) qualify or count as "undead" and that therefore the average Imperial person would not think they would be undead. Pull the other one.))
So with that said...
Is there actually all that much evidence -- real strong canonical evidence, not just inference from stuff like "People will worship gods weirdly and they might still get powers anyway and from this we conclude that gods are just totally shapeable by human thought" or "Well we know that Neferata was totally secretly behind the invention of Shallya (from some obscure line in some book or other) and that can be assumed to be true and accurate and" or some yet another cite from, what was it, Realm of Sorcery or something -- that gods are 'just' sufficient belief and that it's just all about thinking and belief?
Because... I don't really think it's as simple as that. I don't think that even if you did something like convinced enough people of Ranald the Protector being cool and not about revolutionaries, and that this made Ranald change, that this would be sure-kill proof of it either. Because, for example, an alternative explanation could be a matter of politics as it relates between the divine and human society. That... it's not just a matter of going around and thinking it. It's a matter of both god and people and society trying it out. And, uh -- it's quite likely that the god gets a say in this too, you know? (Exhibit A: the worship of Only Gork, and how Mork took umbrage to that. As well as the interesting fact that it took ritual -- it took action, and magical stuff -- to make an attempt at this sort of thing.)
I think... I think Gods and people and society are a lot more complex and complicated than to just easily be able to boil it down as "Humans think: gods result. Humans think: gods change."
I think, that if we wanted to end up with a Ranald the Magician, a good example for how it might happen would be when we stole divine energy from Mork. That sort of thing harkened to (some of) stories told about Ranald. Beyond that one story (which people say "Yeah this proves Ranald ascended" whereas the story itself literally has the storyteller go "But that is a lie that Ranald tells, that he was ever mortal to start with!" so the storyteller himself is going 'Who knows, eh? 's a good story though, yeah?') there's also Ranald being a thief, and Mathilde being a wizard, and having a close relationship with her god, and so on.
Beyond that... it might take something like converting a lot of Wizards (maybe just Grey Wizards) to Ranald worship. Or coming up with, sigh, yes coming up with 'theurgy' and then getting lots of Grey Wizards to adopt it -- thus resulting in an association with Ranald and magic. And also, all those Wizards now believing in Ranald, and also practicing something that was created by a Ranald worshipper. And Ranald might expand from that, or learn magic himself... but it's because his friend Mathilde helped do this, and Wizards started doing this, and so on.