We're having some kind of vision or dream. We don't seem to be much surprised by the trippy stuff that's happening, so we're either asleep and fully subject to the dream's logic or we were expecting something like this, suggesting that this may be a ritual or trial by vision-quest that we're voluntarily undergoing. Most of what we're seeing is stuff that has already happened, but some of it might be things that are yet to come. There's a lot of imagery that might be relevant later or might just be there for its own sake, because it's cool. The reoccurring motifs are falling through air and sinking through water (or perhaps it would be more accurate to characterize it as an absence of solid ground to stand upon?), still images and reflections (portrayal/perception of reality versus what is truly is?), and light/illumination within darkness (pretty straightforward).
We are a very junior member of an order of mystic warriors based out of the Citadel of Daybreak, wielding a weapon called a Keyblade. We, and many others besides, have been recruited and trained by this order in preparation for some prophesied future struggle. Judging by the intro blurb, it's not supposed to go well for us. Our order used to have a single head, the Master of Masters, but he's been gone for some time and now his personal students are running things as some sort of council.
@TenfoldShields seems to have a pretty good read of them, though I'd quibble that Invi might not be actively sowing discord so much as failing to do her duty to quell it or preferentially supporting Ira instead of remaining neutral. If the vision in the first post and the rumors of tension between the factions of the Citadel are anything to go by, we can assume that the coming conflict will be fratricidal. It reads like there's a faction of Ira-Aced-Invi with Gula and Ava either conspiring together or each doing their own thing, but with Ira increasingly isolating himself expecting anything reliant on his leadership to hold together might be misguided.