During SE recent big conference revealing a lot of new things about the FNC games they made a video (in Japanese) about the official mythology of the FFXIII universe and to a larger extent FNC. The mythology reveals a lot, changes some conceptions that the player-base had, & probably reveals what the plot is going to be about in Final Fantasy XIII-2. I have two websites that have this mythology translated though I cannot 100% confirm that either is accurate.

1)Fabula Nova Crystallis Official Mythology

2)Fabula Nova Crystallis Official Mythology 2

I'll also share the link to the japanese video of the mythology here.

This does make the FNC setting more interesting though I had thought it a good premise (in FFXIII) just bad execution. Another thing I cannot confirm are some reports from the Ultimania Omega of Final Fantasy XIII. It is confirmed that it was Etro was restored the party from crystallization at the end of the game, however, as said in the official mythology Etro received no powers from Buniberzei. I do think she may have received some power from Muin when she found her [Muin] in the invisible world.

There was also, what I find, a huge translation error in Barthandelus' reasoning for trying to open the door to the other realm which we now know is the invisible realm: in the Japanese version Barthandelus was not trying to bring back the maker but to open the doors to find & destroy Muin as it says in the official mythology. Thus that would make sense as to the true purpose of the Arks as it said in the Analects that the Arks were there before Pulse was made and were built to fight something from the beyond. That something must have been referring to Muin.

Another interesting note is that Fal'Cie cannot brand L'Cie, that is the function of the gods, however, as we find out in the official mythology the "gods": Pulse, Etro, & Lindzei are just the first created Fal'Cie. So what I'm thinking is that only the higher Fal'Cie - Pulse & Lindzei - can brand L'Cie. The brand is the seal of the "god" & once the seal is applied they are a L'Cie to that Fal'Cie. Thus this means since the party was branded by a Pulse Fal'Cie that means it wasn't anima who branded them but Pulse himself, making me partially right in my topic End of Chapter 2. Where I state that huge thing with the bells was not Anima because the party was sent through another dimension and that in the course of the game no Fal'Cie -besides Barthandelus - had the ability to shapeshift which was apart of Barthandelus' specialty. This may prove that perhaps Anima was not working with Barthandelus - of course this could have been because of a mistranslation - and gave the party a focus to save Cocoon from Barthandelus/Orphan as their focus dream showed bits of the actual ending. Source. Though I have no way to confirm ximaus' translation of the material. The second page is where ximaus comes in.

Also, ximaus - from the gamefaqs link - says that Lindzei was known as the righteous god, the Sage, but called Lindzei a demon after what Barthandelus did; they, humans, had never seen Lindzei. Small side note in the first entry of the Analects, "Vanished Gods" - pluaral - the maker does not exist in the Japanese version of the game it was a term created in the English version. To which ximaus suggests that somebody in the translation process wanted to stay clear of "god(s)". I believe the Luminous God is Buniberzei, while the Stout God is Pulse, Sage God is Lindzei,, & Fool God Etro for she creating naught. I can't remember where I read where each "god" corresponded to in the first Analect.

It is interesting though in the official mythology that L'Cie were created before Etro made mankind. Makes me wonder what were L'Cie before humans? The beasts of the realm or were they lesser mechanical like beings than the "lesser Fal'Cie"?

Ximaus does go on to explain the true cause of the War of Transgression that took place 500 years ago and how Ragnarok saved Cocoon from falling by using the power of Etro. The proof he states is in the 13th entry in the analects which is fairly vague in the Japanese version and even more so in English. Ximaus seems to know japanese & what he says may prove insightful; I'm not a big fan of this game, in fact the story did disappoint me, but with what appears to be a bad job in translating in some parts the game's premise does appear to be getting richer. I can't believe though that it was 2010 when Final Fantasy XIII was released and somebody/SE was still uneasy about putting "gods" in the game; you'd think they would at least come up with a better term than just a singular noun when it was plural in japanese. New translators for Final Fantasy XIII-2 and Final Fantasy Versus XIII please.

Perhaps this should have its own thread but I'll include the Final Fantasy XIII Episode 1 novel that has been translated as well here. Episode 1 picks off from where the game left off and has Lightning trying to find a way to save/return Fang & Vanille back to normal. Lightning also gets a feeling that the fighting is not yet over and that perhaps some people survived all these years after the War of Transgression on Gran Pulse.