Can someone help me?! *Tears hair out*
Okay so back when I was a noobie to this *COUGHnotlongagoCOUGH*
I went to battle Earth eater.
POWNED.
Okay so...
Capturing spree all over Spira for a few days.
I didn't know Catastrophe had 2,200,000 HP.
Go in, hit him for 99,999 A bunch of times + numerous other xx,xxx Damages with my Aeons...
BOOM.
He kills all my Aeons with hundred thorns and does the same to my party.
What can I do?
SOMEONE HELP! http://i206.photobucket.com/albums/bb271/bananasweetZ/Smilies/onion_msn_smileys-21.gif

...Don't even bother helpin me with Shinryu, I'm gonna need another....bazillion levels to fight it. http://i206.photobucket.com/albums/bb271/bananasweetZ/Smilies/cebollita_animated_onion-03.gif

...HOMIGAD!
I JUST GOT 0:0.0 ON CHOCOBO RACING http://i206.photobucket.com/albums/bb271/bananasweetZ/Smilies/w00tsplz.gif

I recommend going to Bikanel Island and fighting the little cactuar dudes (after you do the cactuar sidequest) to get your characters through a large portion, if not all the way through the sphere grid. Celestial weapons and having all aeons are good, too.

Do you have the Magus Sisters? They did a great portion of the fighting for me in the Monster Arena.

@ Olde: Ah, I see.
I did notice Cactuars give quite a bit of AP.

@Erebus: Yes, I have every Aeon including Magus sisters and I am currently sidequesting to get the celestial weapons.
The only problems are with Kimahri's weapon and Wakka's weapon.

1. I'm terrible at Blitzball ;-;
2. THE STUPID CACTUAR STONES DON'T REACT (Or I'm going to the wrong ones...? I've found two already, I think, I could be wrong :X)
Agggggh!!!!!!! http://i206.photobucket.com/albums/bb271/bananasweetZ/Smilies/onion_gifs_emoticons-10.gif

1. Replace all the original Aurochs on your team if you haven't already. Then sign players like Ropp, Shaami, Brother, Wedge, etc. It should be a piece of cake to at least get the Jupiter Sigil, although it might take a while.
2. Use a guide for the cactuar sidequest
3. There's a really good map on gamefaqs.com that indicates the locations of all the blue and red butterflies in the mini-game in Macalania Forest. I couldn't do it either, until I found that map.

1. That must be why I kept losing :X
2. By cactuar stones I meant the things in ThunderPlains where you press square, if you thought I meant the Desert quest; I'm almost done with the desert/Cactuar quest... .__.;
3. See Above, I haven't got the weapon yet ;-; ^
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3. See Above, I haven't got the weapon yet

Well, you're going to need to power it up somehow. If you're telling me you got the Saturn Sigil but not the Spirit Lance, that's just really weird. Equip a weapon or armor that has No Encounters (well, I guess you don't have to, but it's easier) and run around the Thunder Plains pressing [square] to all the cactuar stones, then press [square] at the pillar on the right side of the first section (closer to Guadosalam).

I almost finished the butterfly quest but I got confused and kept getting in battles till my stupid time ran out.... http://i206.photobucket.com/albums/bb271/bananasweetZ/Smilies/sweat.gif
About the "No Encounters" Thing, I have an equipment with that and only unequip it for monster capturing.