Quote Originally Posted by Tabris View Post
When Tidus fades away?
Not Tidus' end.

Quote Originally Posted by Firenjar View Post
Is it when Yuna is,for lack of a better word,killing her aeons?
Nope.

Quote Originally Posted by 4evarisha View Post
The Final Aeon getting it
Again, no.

Quote Originally Posted by Firo Volondé View Post
Quote Originally Posted by BG-57 View Post
the answer could be described as dark, frightening, and tragic.
Most events involving Seymour could fit the bill, especially your last battle with him. Is that the answer, or if not, is it anything to do with Seymour?
It's not the answer, but yes, it's related to Seymour.