I was wondering... Maybe Episode Aranea took place in Cartanica and Gralea, that's just my thoughts.
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This screen comes from the 2014 trailer and it seems Cartanica, in these days they trying to update this place with new street and other stuff, we know that Episode Aranea took place in Niflheim and we know also that concern the "worst day of her life".
In Episode Duscae there's the typical blood moon (probably connected with the plague) and the weather in general changes when you go far from the map with the glitch (near Lestallum)... From Episode Duscae they retrieve some things, like the "chain combo system" and who knows, maybe the red sky and the blood moon too with Episode Aranea or Ardyn (but probably this one took place in Lucis).
I've edited the screen making it black and white to see better the objects, that monster near Noctis seems a Sabertusk, typical in Lucis, but we can see that "flying thing monster/daemon" only in Niflheim and that structure is like the others in Cartanica lel.
Ps. Sorry for my english.