This was my group for Necron:

Zidane
Freya
Quina
Amarant


Make sure to have high TRANCE, then use every ability in your arsenal, This was what I did:

First, Zidane used Grand Lethal
Second, Amarant threw an item.
Then I made Quina use Frog Drop
Then I had Freya used Spear.

That tacked off a lot, repeat, however, have Zidane attack with all he got and make Freya jump if they're not in TRANCE. Make Quina, Amarant, or Freya heal when needed.

Equip these skills:

Auto-Potion
HP+Whatever
MP+Whatever
Any status immunities you can use.

Equipment:

Anything that effects conditions or attributes, and use the strongest weapons and armor.


That's what I did.