Often times, one must fight a GF before they are to join your side, but there are a couple of other ways you can acquire them as well! For instance, you have to catch the Cactuar King before you can fight him, and you have to go out of your way to find the ring to draw Alexander from.

I loooved Odin's quest. The countdown, the little tasks with the demons, etc. That was perhaps my favorite. I'm also fond of fighting Cerberus, and fighting Ultima Weapon to acquire Bahamut.

What GFs were your favorites to acquire and why?