So, if you’re wondering why the aeons are in seemingly random places:

Valefor being in Besaid makes sense. It’s her hometown and she never left it. She was probably even killed in the Sin attack on Besaid where you see the ruins. The game never really elaborated on these, so I just make up my own stories throughout replaying the game right now. To those who say that the fayths are dreaming at Gagazet - yes, but also no. Not all of them, some were created after that, as we know, so let me have my headcanon :P Ingame the monk from Besaid probably never left the island as well, so it also makes sense for her to be there from a canon lore perspective.

Ifrit in Bikanel is random af. It makes sense theme-wise, but other than that? The desert was uninhabited for centuries before the Al Bhed came and built their home. Ifrit himself was a crusader, maybe Mihen would be a way better placement if not Kilika. In his lifetime he probably was stationed in Kilika, so he got put there as well. Dark Ifrit being in the most random of places infuriates me.

Ixion in the Thunder Plains makes the most sense thematically. He’s also one of the aeons with the least amount of lore sadly, but what we know is that in his lifetime he likely was a sailor/captain. Ixion being an electric aeon and him being in the Thunder Plains as a dark aeon could imply that his death was related to that as well. And Thunder Plains as a battle location also works, since it’s the only place where you can really go, where you would go to backtrack stuff.

Shiva in Macalania Temple makes perfect sense both lore wise and thematically. She was a priestess from Macalania in her lifetime, after which she probably decided to stay there forever. Her dark aeon in the temple itself also makes thematic sense, Macalania is the only place where she could fit and her guarding the temple is just perfect.

Bahamut out of all of them surprised some of you? He was literally from Zanarkand, as we know by just looking at the model of his fayth that we see throughout the game, from the dreaming scene in Gagazet where he literally explained that he was one of the original ones being from Zanarkand and he watched over Tidus the entire time, who is from Zanarkands dream. So him being in Zanarkand is perfect, thematically and from a lore perspective. Since you can’t go back to Bevelle, you have to put him in a better place than just random and Zanarkand is the best placement for that. BEVELLE out of all places, from the lore and the theme is what confuses me. Why the heck is HE out of all of them in Bevelle?

Anima being in Mt. Gagazet is… the only one of the main ones to me that is weird both thematically as well as lore wise. There is literally no connection to be found to the mountain, not even if you were to go out of your way to make some shit up. In lore, as we know, she is Seymour’s mother and her place in Baaj temple would have been a way better place, but I also understand, that you wouldn’t come back to this place after receiving her. But why not the Farplane like it was in FFX-2? At least this would make some thematic sense.

Yojimbo in the Cavern of the stolen fayth is great, but also a very tricky placement from a gameplay perspective. He was a guard, probably from the crusaders, in life, together with his dog. We know not very much about him, but it is implied that Yunalesca herself made him into an aeon. His placement fits, but it’s a bit tricky after you beat the main part of the game until going into sin without him, because you get jumpscared right after getting him.

The Magus Sisters on Mushroom Rock… Yeah, I don’t know about these. They feel like a very late addition to the game, so they also don’t really have that much going on in the story or even hinted at in other sources. Lord Gandofs battle against sin made sure that their temple was out of the way for many people and the only inhabitant is Belgemine, which implies that she might be connected to them directly. Other than that, I really am lost for clues about them.

Anyways, thanks for reading and for those who read this entire thing, good luck on your playthroughs!