It's just the sequel to final fantasy XI from tidus being kiddnapped and its just yuna , riiku, and pain ( the new girl) they're disgused as sphere hunts trying to find tidus and spheres because she...
It is simple. Load your game, and then go to the main menu. Press triangle, which opens up a list of all the characters you have unlocked. Once you've decided which character, press x and x again...