Okay, there is a LOT to unpack here this time!
I think Darkness is not a "who", but an "it". An ethereal being. Darkness is not any of the existing characters we know so far.
I agree with you here. I don't think Darkness is necessarily the whole "element" itself, but more so a materialization of conscience through it. Sorta like how we have the Princesses of Heart, beings with a heart made of pure Light, and then Ventus and Vanitas later on as artificial pure Light and Dark, respectively.
Wheter they are a whole new character or materialization of the Darkness from a bunch of characters is yet to see, but I don't think this is a Vanitas case.
The big problem with this is that it redefines the concept of darkness in the whole series. For example, it throws Riku's whole story under a bus: What is the point of understanding your weaknesses and learning to control your own darkness if you end up being possessed by such beings anyway?
It doesn't in the slightest. A incarnation of Darkness having a will of it's own doesn't change anything about Riku. Plus, he's also the first character we know for sure that has control over his own Darkness, so I doubt this character could have possessed him either way. lol
So somehow the player character lives on through Xehanort, and now Xehanort is becoming obsessed with defeating the darkness eventually leading him to reenact the Keyblade War which is all part of who's plan? The MoM.
Not really. Both Xehanort and Eraqus seem to have memories of the UX time, and it's not limited to the player character alone.
@ thread
At this point, I wouldn't be surprised if Ava is Darkness, althought I don't think that is really the case. MoM made it pretty clear that with his talk about a lifetime that we could be experiencing more than what we assume;
I feel like we could be experiencing a second timeline. That at some point the story flowed in such ways that the MoM never left his students, the Keyblade War happened another way with more casualities, with a lost character that ended up becoming Darkness. That person could either be another Student of his or maybe another Master.
Then the MoM traveled back in time and made a plan to change everything to another path for whatever reason, which is why he is so keen on following such a specific plan, with all the planning ahead, the eye of the beholder and so on.
I think that one theory that Darkness is a part of the MoM that was left behind could be tied to this, somehow.
In the end, Sora is not the MoM like some theorize, but he could be a parallel to him as another character who went back in time to alter the flow of destiny.
I wouldn't be surprised if the plottwist of Dark Road is that Xehanort would end up doing the same thing, only for his classmates to still be lost in the end, causing him to go down the path of Darkness until he becomes the disgusting bald man we all hate.