Yeah, when I think about it Valhalla was said to be on the borders of the Unseen Realm, which is very similar to the the Final World. And how Chirithy says "there's nothing else beyond this". Makes me suspect what we saw in the secret movie was the Kingdom Hearts equivalent of the Unseen World, maybe it's the Kingdom of the Dead being ruled by Yozora? And in FNC, Chaos is visualised as dark water in Valhalla, the Verum Rex art shows Yozora's swords sinking into water, as well Young Xehanort warning Sora he'd be condemned to the bottom of the abyss, so a lot of signs seem to be pointing in that direction imo.
Yeah, there's a number of reasons to think that the secret movie might have taken place in KH's equivalent of the Unseen World -- which will probably be called the Abyss -- not least of which are the connections to both Versus XIII (the Tokyo Government Building) and TWEWY's Shibuya (most obviously the 104 building).
I'm not quite so convinced that Yozora would be the king of the Abyss rather than another denizen who Sora and Riku has to help, but there definitely seems to be a connection between the Noct expy and the Abyss. XD
I'm not quite so convinced that Yozora would be the king of the Abyss rather than another denizen who Sora and Riku has to help, but there definitely seems to be a connection between the Noct expy and the Abyss. XD
And the crystal acting as a gateway to the beyond makes much more sense actually, with the beyond serving a similar function to Valhalla in XIII and the Final World in Kingdom Hearts. The crystal is a little bit like Etro's Gate in that context.
The Ardyn thing's still a bit murky for me but I can buy what your saying, especially since he was the one mostly responsible for spreading the plague across the world in the modern era, destroying his soul may have undone that. But also the crystal being destroyed in DotF and purging all of the darkness with it's light and shattering is a clean explanation that I actually prefer, does it do that in the original ending or did it just fizzle out?