in Balamb Garden there are people that u have to challenge to and after them all ull get gilgamesh

U MUST WIN 15-20 BATTLES WITHIN BALAMB GARDEN BEFORE THE CC MEMBERS WILL CHALLENGE U!!!

if u want help on this really annoying side quest than refer to this
http://guides.ign.com/guides/3847/page_6.html

NOTE**some people wont appear automatically
u have to keep going in out of the screen until finally the person u want will appear