How to Defeat Materia Keeper in Final Fantasy 7

Fill up your limit break gauges by fighting weaker monsters on Mount Nibel before attempting to fight the Materia Keeper. Having three characters prepared to use their limit breaks right away will make the battle with the Materia Keeper much simpler.

Cure the members of your party and initiate the battle with the Materia Keeper. Do not use any fire-based attacks on the Materia Keeper. They will only restore its hit points.

Use all of your strongest limit breaks on the first turn. Aires' Seal Evil limit break can stop the Materia Keeper for a few turns. Be warned, however, that Vincent's level one limit break is fire based and should not be used against the Materia Keeper.

Cast Bio on the Materia Keeper during the next turn. Once the Materia Keeper is poisoned, it will lose around 200 hit points every turn. Don't bother with other status-changing attacks as the Materia Keeper is immune to the majority of status changes.

Cure any party members who get hurt during the battle with spells like Cure 2 and White Wind. Keeping your characters at or near full health is important when fighting any bosses in "Final Fantasy 7."

Continue to attack the Materia Keeper while curing your party members. Physical attacks work well, as do summon monsters other than Ifrit. Once the Materia Keeper begins to weaken, it will begin to cure itself. At this point, put all of your effort into inflicting damage on the Materia Keeper until it is dead.