An 'automatic' strategy should involve Sneak Attack. I suggest

Comet=Sneak Attack
Comet=Quadra Magic
Comet=HP Absorb
Comet=MP Absorb
Mime=Final Attack
Mime=Counter
W-Magic=Cover

If there's a single target at the beginning of battle, that's a potential 159,984 damage without pressing a single button. Then W-Magic it from then on for 319,968 damage. Each hit incurred would result in another 319,968 damage.