This is actually a really simple encounter, but it seems many people are struggling with it.

At the start of the fight switch your paradigm to Medic – Medic and continue to heal, typically he targets only one person and sticks on that target; if he is targeting Hope then be sure to start casting your heals before he attacks as Hope will take big damage.

Once Odin uses his shield ability (it will indicate he is using a shield in text above his head, and he will be standing still not attacking) switch the paradigm to Commando – Ravager and spam your auto-attack.

Keep repeating these steps and you should beat the doom timer in no time!

I did this and finished with a five star rating and didn’t come close to dying once.