Guardian Force Home / Quezacotl / Shiva / Ifrit / Siren / Brothers / Diablos / Carbuncle / Leviathan
Pandemona / Cerberus / Alexander / Doomtrain / Bahamut / Cactuar / Tonberry / Eden
Odin / Gilgamesh / Phoenix / Chicobo / Minimog / Moomba
Basically, to get Odin you have to complete a small sidequest. For that, you have to visit him in his tower on the Centra- continent: the Centra ruins. What you have to do there exactly is explained right here in the side quests-section. Odin can't be controlled. He appears randomly in fights (though not boss fights) at the very beginning and kills all enemies in one hit! I also noticed he likes to appear when enemies are in very high advantage (or very strong at least). Almost every time when I was fighting a Malboro or a Ruby Dragon, he appeared! It was quite a nice way to level up.