Sora and company in Kuzco world (yes even the world is named after him). The lama emperor has learnt his lesson and they're on their way to the palace. Ava, aged considerably from her wanderings in the sleeping realm, finally makes her move. Stopping Sora and the keyblade wielders outside the gates, she lets Kuzco and Pacha by.
The group stands ready for battle, but is shocked when the foreteller makes no move to fight. They ask her "aren't you here to stop us?" She replies that she is, but there is something she'd like to try first. Summoning a barrier she separates Sora from his companions. Before the boy can retaliate, she uses illusion magic to draw him into his alien memory.
He is next in a scene of Scala Ad Caelum. A younger version of Ava tells him that she senses a door was opened to him (his connection to the gazing eye). Due to this, she wants to try convincing him of the horrors his actions would bring.
The world begins to move as a scene of a young Eraquos is setting up a chess game. In walks in a young grey eyed Xehanort, back from his travels. The brunette tries to welcome him with a hug but Xehanort's foul expression gives him pause. He asks what's wrong; Xehanort replies that "he's just here to see the masters". Eraquos offers him a game of chess all the same to catch up. Xehanort rejects a little more forcefully.
At this point master Ludor (Luxord) comes in, offering to stand in for Xehanort after the meeting. Though hesitant, Eraquos agrees and they all leave the room with their master.
The scene suddenly changes as No Name is summoned by one of the 7 masters of Scala Ad Caelum in a council chamber (much like the one the nobodies would eventually make) as part of a demonstration of arms. From this vantage Sora watches as Xehanort makes his case to the council about resetting the world line (the light is too corrupted for this reality to be good). The masters outright deny his suggestion (he does not have appropriate insight or knowledge into the nature of the universe). Xehanort calls them corrupted cowards and leaves.
Scene changes back to the game room has No Name is desummoned to the mantle. Xehanort angrily enters and begins pacing. A young Yen Sid (still a keyblade master) notifies the man that the key archivist wishes to meet with him. The seeker accepts with a dismissive wave.
In comes an elderly man sporting a kind smirk. He comments about overhearing the meeting, and how interested he is in how Xehanort came across such "insights". Xehanort rebuttals that it's none of the man's business. The visitor merely chuckles and grasps the younger wielder's shoulder with deceptive strength. "I think you might be mistaken about that".
Before Xehanort can pull away the Librarian's eyes turn an iridescent yellow. "Try to cover it up all you like kid" the elder taunts, "but You're heart's has some seriously dark deeds buried inside" (referring to the events of Xehanort's time-traveling). "Besides," he continues, "I have a lock that LITERRALLY has your name written all over it. So hopping into you might be just what get it going."
The old man begins to perform the same spell of heart transferring that Xehanort did in BBS. But before he can complete it Eraquos walks in, and seeing a his friend about to be struck by a spell, jumps in and slices the intruding heart in half (though half of it still lodges itself in Xehanort and knocks him unconscious).
Shocked by seeing his heart split in twain the man falls to his knees and begins to disintegrate. He looks to No Name on the mantle knowingly and whispers "So this is the one, huh... Master?" And he consequently dissolves completely, soon to be reborn as Xigbar.
Master Ludor and Yen Sid burst in after hearing the commotion. The former rushes over to where the librarian once knelt muttering how this wasn't supposed to happen. Eraquos, who was in the process of moving the unconscious Xehanort to a couch, draws an unfortunate conclusion from his master's display. "Master Ludor?" he asks hesitantly, "Did you know he was an agent of darkness?"
Ludor looks back to his student with a frown. He tries to assure him that the man was not an agent of darkness (in fact he was a vital agent for the universal order). Eraquos shrugs it off and proclaims that Xehanort was right about the corruption, and that he will no longer have a part in it. As the young man leaves the room his master asks where he's going. Eraquos replies "to start over without your poison".
Ludor follows after his student as he tries to sense into him (the sound of Eraquos flying away sounds in the background), leaving Yen Sid and Xehanort alone in the room. The young sorcerer, having decided to leave the order completely, moves to the mantle and reveals a secret compartment containing a Book of Prophecies. But just as he's about to retrieve it, Ava apparates and stops him. The now aged keyblade mistress tells him that the book (as well as it's siblings from the dandelion masters) are fakes. Handing the young man her copy she explains that "This copy, on the other hand, can let you change the future". Before the man could respond, the interloper vanished.
Yen Sid, deciding that this wasn't the time to question his fortunes, takes his leave from the world (beginning his own quest for improving the future).
Now that everyone has left, Xehanort finally opens his now yellow eyes, and armed with the dark knowledge carried by the half of Luxu's heart he claims No Name from the mantle and plunges it into the ground. From his view from the gazing eye, Sora bears witness to the destruction of Scala Ad Caelum (and almost everyone else on world, civilian and wielder alike), as its barrier against darkness is dispelled by the corrupted keyblade wielder, and his vision is consumed by a familiar void.
Sora reawakens to the aged Ava standing over him, asking the boy if he understands why he must not awaken. "No matter how often the keyblade wielders rebuild" she continues, "your darkness always finds a way to tear it apart again".
Sora's angst nearly takes hold, but as always, his friends break through the barrier and snap him out of it. Standing between the ancient master and their best friend, Riku and Kairi confirm that Sora will never become evil, for "he has too much love in his heart to become that way".
Ava tries to brush off the claim saying that such aspects will inevitably disappear. This fails to dissuade the friends however, stating that she clearly doesn't know Sora. This proves enough to rekindle the spark in Sora, and along with his companions he finally faces off against Ava.
After a taxing battle that puts the trio to their limits, they defeat the embittered keyblade mistress. With her ambitions put to rest, Ava admits to her long held doubts about defying her fate. Sora, ever the pure hearted hero, comforts the aging woman as time finally catches up with her. "You know," he says, "even if I am stuck, and end up doing the exact same things the other me did. I'm looking forward to actually meeting you".
Caught off guard by this testament Ava asks him how he could even say that, especially with everything that's just happened. His reply: "I'd like to get the chance to see you happy". Reminded of why she gravitated to the master in the first place, she can't help but let out a tearful smile. "And to think, I wished for everything to just go away..." Ava finishes, fading into golden dust as she finally let's go.
Sobered by their experience, the party finishes in Kuzco and takes their leave; weighed down by the knowledge this experience has exposed them to.
A/N:
Hoo boy, this was a brick even in summary. Suffice it to say I am now going into uncharted waters by creating the inciting conflict of Xehanort's career. I hope that I was able to create a satisfactory explanation to the disappearance of Scala Ad Caelum, as well as a fare conclusion to our prodigal daughter Ava.
I have no delusions that I have left a lot unsaid about lore. So if any of you have questions or comments PLEASE let me know. The last thing I want to do is leave anyone (unintentionally) confused.
Also, in game this would unlock both the KUZCO and Ava's keyblades. In the spirit of the movie the KUZCO keyblade is just as golden and Kuzco'y as everything else that was Kuzco's. As for Ava's keyblade… well, you all know its design, and the significance that using it would hold…