This is one of the toughest side quests in the game. Defeating the WEAPONS.

¤ Emerald Weapon

This is the 2nd most difficult Weapon to defeat. You must have equipped FullCure and Magic Counter together, Final Attack and Phoenix. And you must have equipped Underwater Materia (Click here how to get it), because then you don't have a time limit of 20 minutes. Also have 4x Cut, Slash-All, Regen. The strongest weapons and you must have 9999 HP and 999 MP and a strong attack power. Attack him with all you got. When the balls comes, strike them first, because they can drain your HP and MP.

¤ Ruby Weapon

This is the most difficult Weapon to beat. In the battle the Weapon swaps two members away so you must have one party equipped with the strongest materia. I recommend Cloud, because he have the level 4 Limit Break: Omnislash. Equip also Knights of the Round, Final Attack combined with Phoenix and Magic Counter combined with FullCure and a strong attack power, HP and MP are also recommend. Knights of the Round must have a lot of AP learned, or be Master. When the 2 other characters are away do only this two attacks: Knights of the Round or Omnislash. Because they are the strongest.