Started messing around with Earth teams to try and take on Odin with. I have 2 things on this:
Thing 1: I really hate these fights. End game fights in this game are absolutely horrible. 95% of enemy attacks are either piercing, multi-elemental, ignore blinks, or have stupidly high multipliers. And more often than not, all of the above. Add in the other BS like starting the fights with 2 stacks of imperil on you, or Doom, or insane damage/defense boosts and they're just straight up not fun. On a minorly positive note, since half the attacks ignore blinks, the mirror image gimmick is easier to sustain.
Thing 2: Holy **** Kelgar. Calm down man! USB + AASB is an insane amount of damage. Got Earth weak Odin to 60% just with Kelgar alone (Galuf, Dorgann, and Tyro got wiped pretty early). With that combo, Kelgar does 7x2+8+8 (30) attacks per turn. Dorgann would be doing 4x2+6+6+imperil if he survived. Pretty dang good dps if I can get past the BS damage from above.
TL:DR - End game in FFRK is utter crap.
Edit: Also Magia. Screw Magia