
Originally Posted by
Brightshadow
Well... that last part of the video is from Final Coils of Bahamut turn 12 after you defeat it.
SPOILERS::
Louisouix is actually alive in a manner sort of. You see signs of him in the Binding Coils of Bahamut in the very first turn, you actually talk with him after defeating Turn 9 in Second coils, and he is the main boss "Phoenix" in Turn 12, as he has been turned into that primal and is currently tempered by Bahamut himself. That last part shows what happened to him, and how he became Phoenix and was able to stop the full brunt of Bahamut's attack.