elchebib wroteGet the growth egg as early as possible. When Vanille learns the Death spell, go to Ochu (the plant with the tentacles) in the special missions (you need a chocobo to get there) and put on the defender classes and have Vanille spam death until it connects. You'll then get the growth egg.
I just killed him with an extremely weak party ( 4k-ish HP). Cast Aegisol and Fortisol before battle, and had a Vanille-Snow-Hope lineup on Sab/Sen/Med. When I get the lucky Death stroke (luckily, I already had the Marlboro Wand) on Ochu, I'd imperil all his minions, then spam Firaga. By the time the Aegisol and Fortisol lose their effect, I'd lost the haste advantage (Hope hasn't learned Haste yet .. like I said .. party was extremely weak) ... I brought in the Vanille Summon to clean them up.
An overall fun battle.
I hate grinding in JRPG's btw. Having underleved characters makes battles more fun, challenging, and makes you come up with creative ways to slay hardass bosses, instead of doing whatever they recommend in walkthroughs. :)