Quote Originally Posted by Behold the Floyd
Gunner is Moogle, Juggler is Moogle, Sniper is Viera, Defender is Banga.

I believe Juggler requires two Thief abilities, Sniper requires two Archer abilities, Gunner requires two Mog Knight abilities and Defender requires two... well, either Warrior or Monk abilities. I think it's Monk.
Mog Knight actually reguires 1 animist which is weird. I think MK and Gadgeteer should be switched in requirments and positions.
I once made montblanc a gunner for a dispatch mission just to find that I can't use him!