Possibly the hardest battle in the game which is not helped if your team have depleted SP and MP from the previous battle. The Gaia Core is very durable and has a HP set at the limit of 9999. In addition to this all parts of the final battle have a varied resistance to all magic.
The player will want to throw their best attacks at the boss until it falls, Liete can help with healing when needed. The player should try to eliminate the Mega Gaia before they spawn Gaia Tentacles, when multiples are summoned they can deal devastating damage to your party.