ok, this has been bugging me for some time:
Aizen has been in heuco mundo for about a few months right? And within that time he has created arrancars using the hougyoku. Fine. But the current no-5 espada says that Nel has not entered Las Noches for years (292, pg. 7), and saying that the number on her back is now meaningless (the numbers are said to be given by Aizen). If she's created by Aizen, who has been there for months, how is she able to have left Las Noches for years?

This post has been edited by cyhborg: Feb 18 2008, 03:30 PM

But that would mean Aizen was in Heuco Mundo all those years back since Nnoitra and Nel were already ranked in the flashback scene. Maybe during that time Aizen was travelling to and fro between the worlds *shrug*