You need (in my case) X, Axl, and Zero(You'll need Absolute Zero for this.). Wait until your characters are all at 100% WE, using your sub tank when you need to. When they are all at 100% WE, go into hyper mode and unload on Rafflesian.If Rafflesian is somehow still alive, then switch someone out with Marino, and use her Hyper Mode to finish her off.

ive tried ma best to beat her but her sunburst attack kils u.can some one tell me an easy stratagy to beat her plz

The way I beat her was gotten all of Zero's command arts (the last 2 that you have to gain), and Massimo's 3rd and 4th beserk charges.

I brought in X, Zero, and Massimo. Get all of their WE up to 100%. Switch them to their hypers modes. Then when your turns come up, use the Zero Skull Crush (you get this by using his action trigger 999 times), Massimo's Beserk Charge action trigger, and X's Charge Collider action trigger. But make sure you take out Rafflesian before you go after the Belladonna's because she is more of a threat.

I got X's ultimate armor while I was still working thru the Gimialla Mine before Spider goes away...so it does work!

Hope that helps!

get as much sub tank that you can and put in zero axl and m***imo. put them in hyper mode
and use the action trigger as much as possible. hope that this helps you.

I managed to do it with X, Cinnamon and Zero with Berserk Protection and FMs and Sub
Weapons that help raise your WE equipped (X had Block All on, so he was safe to begin
with). Use the Absolute Zero and Fire X hypers and wail on her while Cinnamon uses her
Action Trigger and Sub Tanks when need. She'll fall easily. Just remember to save the
Belladonnas for last and keep yourself healed

X with "Turbo Buster" main weapon and two "Generator" sub weapons. Zero with "Z Rapier"
main weapon and two "Generator" sub weapons. Marino with "Beam Wonder" or "Beam Wonder S"
main weapons and two "Get EXP +" sub weapons. And if you want to fight Rafflesian first,
before dealing with Incentas in Gimialla Mine (Chapter 6), have Spider equipped with "Ace
of Spades" main weapon and two "Get EXP +" sub weapons. These characters must be equipped
with "Berserk Protection" and "End To All" (don't equip Marino with it) Force Metals.
First, ignore the two Belladonna (Level 44, 20500 LE, 4000 EXP), start using Zero's two
'Generator' while in Black Zero form and then, activate the Action Trigger and use only
the Zero Skull Crush (acquired after performing a total of 999 successive hits in Command
Arts) against Rafflesian by at least 6 or more hits, after that, use X Fire's Charge
Collider (make sure X has equipped the "End To All" Force Metal), and if it reduces her LE
to 1, you'll enter the Final Strike mode (your three characters must be alive), cancel it.
After that, first, in a Marino's or Spider's single turn, use your two "Get EXP +" sub
weapons (this sub weapon boosts 10% of EXP on a target ONLY as a finishing blow) only on
Rafflesian, then, finish her off with your "Beam Wonder", the "Beam Wonder S" (these two
main weapons boosts 100% of EXP on a target as a finishing blow), or the "Ace of Spades"
(make sure your WE is at 75% or higher) as well. With it, you'll obtain 48400 EXP from
Rafflesian (22000 EXP+120%). After destroying her, try doing the same thing on those two
Belladonna (4000 EXP+120% of EXP= 8800 EXP). You'll obtain a total of 66000 EXP
(48400+8800+8800) and the X's second Hyper Mode, the Ultimate Armor.