Birth by Sleep Reasonable theory

the shadow dude from the FM+ Secret Ending could be the first fully consumed heartless. he is vanquished in BBS and his heart returns to his nobody (possibly the only nobody, maybe his heart knew where he was) and over time he becomes whole again. he relearns the power of darkness(somewhat), teleports to hollow bastion and hits his head falling out of a dark portal in the sky. ansem the wise finds him unconscious and is the Xehanort we all know. he didnt lose all his memories tho, and is easily consumed by darkness b / c his past.

thoughts?

 

Seems weak, and somewhat superficial if you are assuming that Xehanort magically gets amnesia.

 

he didnt learn his power completely yet, so he portaled to the sky and hit the ground on his head.

edit: i mean he didnt have full control yet

 

If you are referring to the apprentice that wears a Dark Riku sort of costume with a helmet... the theory that he is possibly 'Xehanort' that Ansem the Wise took in has already been thought of. He is a likely candidate as is Terra right now.

 

It's a working theory that has some possibility. Unfortunately, we can't be sure yet. You may want to browse around and see some of the other theories on the Apprentice, Terra and Xehanort here. There are some interesting debates that have gone on concerning the theories.