not everyone was real thrilled w/ the battle system, the menu is a lil confusing at first. (I dont play fighting games or Mario, I didnt even know which buttons were s'posed to be A B C ^_^; ) After a couple fights I got it figured out, after a couple more fights I figured out Break, Down and Air. from then on I just slaughtered.

Down
chaos and Ziggy can do hella damage to a downed enemy. Both have ether attacks (aura and fire) Have KOS MOS, Jin or Jr. break the ememy while ya boost chaos or Ziggy. Boost the other guy while you unload a stock of the circle button; the enemy goes down and then gets smacked a couple times. The next guy comes in and does the same thing. If the guy is still alive KOS MOS minigun does nice damage as does unloading a birage of bullets from Jr. (piercing attacks)

Air
Jin, KOS MOS, Shion or MOMO for ether attacks or Jr. for piercing. Same senario for a downed enemy. Jin or KOS MOS flings the enemy up in the air, boost one chara after another and unload your stock of the circle button, you can always save one stock on KOS MOS and when the enemy smacks the ground she can minigun his ass.

Ether/Double ether
Ether is not really all that effective unless: You are attacking from behind. The enemy is in break and preferabally up in the air. Ether is most effective on a enemy(s) up in the air. Hit an ether bonus, boost someone (usually I just have chaos boost himself cuz he's got lotsa ep) It's the best time to cast the double medica 2 if ya need it or hit all enemys with an ether attack.

Character Double Attacks
For taking out a single enemy quick or putting a nice dent in a boss' hp:
Have the person innitiating the Double behind the enemy (when possible). Have someone break the enemy and fling em up in the air or down and boost the chara behind the enemy. Cross Fist, Silver Duet or Ice Brand can usually kill an enemy in the air.
I used Elemental Nocturne or Angelic Requiem to kill multiple enemys on a skill pt bonus :meh: