Today, it's "Clash on the Big Bridge"!!!
It is the official name of Gilgamesh's theme. It first appears in Final Fantasy V, and its remixes serve as the theme (if there is any) for all later appearance of Gilgamesh. It is a music have energy, excitement and a little humour, perfectly describes the warrior that is Gilgamesh. Believe solely the honour of swordsmanship (and swords), he will join sides of our heroes to combat the evil of the world, even though he was working for that same evil (i.e. Exdeath).
Reference:
http://finalfantasy.wikia.com/
Alternative Hearing:
http://www.youtube.com/watch?v
http://www.youtube.com/watch?v
http://www.youtube.com/watch?v
http://www.youtube.com/watch?v
