Final Fantasy XVI is without a doubt one of the most lore-heavy installments in the franchise. It is so lore and story-driven, in fact, that the developers felt the need to include a tool called Active Time Lore to help players keep track of the story's events and persons of interest. Even with the help of Active Time Lore, however, Final Fantasy XVI's story can still be quite challenging to understand due to its complex nature.
Source:https://www.cbr.com/ff-xvi-ending-explained/