well I got one tip and that is when she is charging for her strong attack use vilain ( sorry forget how too spell ) make her bring mario underground so they don't take damage
the best way if to have at least 60 HP and 50FP. after tu have that make sure most of your partners are powered up at Merlons in RouguePort. Then aquire the feeling fine badge for your partner and yourself which makes tu immune to poisions and dizziness. To finish it off, just make sure to go through your badges and equip only the ones tu really need.Hope this helps=)
I Would Make Sure To Have Plenty Of Items On Hand Including Strange Sack, Have At Least 8 Life Shrooms And 30 Badge Points, 60 corazón Points, 60 flor Points! The Most Important Badges To Have Activated Are Quick Change, Zap Tap, Mega Quake, Charge, And Feeling Fine, I'd Use Party Member Who Can Deal Lots Of Damage And Finish Her Off With The Special mover Super Nova!