In Story Mode, the party starts off on a platform far away from Great Galdes, flanked by three Thunder bombs and a crystal. The crystal will use level one magic like Thunder and Blizzard. Destroying the crystal will dispel the barrier to the next platform and two crystals will have to be destroyed to reach Great Galdes. On the third platform the party will fight Great Galdes.
Great Galdes is assisted by four crystals which use tactics similar to the two on each of the previous platforms. Great Galdes himself uses high level, area-reaching magic. He may cast Graviga halving the target's HP and leaving a gravity status (especially problematic if players land in the depression near on the southern part of the platform). He may also cast Quaga, which has a large attack radius and may either stun or flip the target(s). He may approach players and scratch them or spawn new crystals.
Players that jump on him or the pedestal he is on, may have Meteorga cast, which can kill the target regardless of level if two to five connect. The pedestal under Great Galdes has spike like protrusions that can be hit (just attacking the spikes will not harm Great Galdes) to open his second mouth revealing a small red crystal. Attack the weak spot quickly because after a brief pause he may close his mouth and continue taking reduced damage. After dealing sufficient damage Great Galdes will destroy the platform and the second part of the battle will begin in midair.
Great Galdes does not change much but he no longer spawns crystals. He does however have a devastating red laser which is capable of dealing 1000+ HP of damage (survivors are left with the Doom status). While striking the crystal is still effective, be cautious, because if the crystal shines, Galdes will fire his laser attack. When his HP hits 0, he will revert to his regular form.
At this point the player must cast magic on each of the rings, one for each teammate (a maximum of four rings). Revive any dead teammates with a Raise spell, the magicites on the field, or Phoenix Downs scattered around. If the outer rings reach the ring trapping a weakened Galdes he will transform back into Great Galdes. If too many tries are unsuccessful in Story mode, a moogle will attempt to write a sign hinting how to defeat the enemy, but it is spotted and tries to tell a hint to make up for it.