Instructions
Press "L1" in the field before the Odin save point and select "Shrouds" to use for Lightning and Hope. The protective Shrouds, like Shell, Vigilance and Faith are best because Odin casts Doom as soon as the fight begins.
Select the Medic/Synergist paradigm and at the start of the fight, buff both characters with more protective spells. After the first few rounds, shift paradigms to Ravager/Ravager to damage Odin, but don't rely on this.
Make use of the Medic/Medic paradigm for Lightning and Hope. This is for two reasons: Odin's attacks are very powerful, but healing raises Odin's Gestalt meter. Once the Gestalt meter fills, tap "Square" or "X" on the controller to capture Odin.