Ah, now we're getting somewhere. This is a pretty simple floor. In the southern hall, there are three caverns. The first has a save point, which you will definitely want to use. The other two hold Treasures guarded by nasty bosses. And if you continue on, you will enter the crystal area where Zemus waits.
The middle cavern holds the Holy Lance, guarded by Plague. This guy is basically a Veteran on steroids. He will cast Doom on your entire party, giving you a ridiculously short time in which to kill him. Bust out the most powerful attacks you have—this is like fighting Odin, only he has more HP and no easily exploitable weakness. Throw Fuma Shuriken at him, summon Bahamut, have Rosa wearing the Minerva Armor firing Artemis Arrows, do whatever you have to. It won't be easy.
The east cavern holds a pair of Ribbons, guarded by a pair of Lunasaurs. These guys will cast Wall on themselves and bounce extremely powerful Bio Spells onto the party. The Walls make it difficult to concentrate on one or the other with Spells, but Baham doesn't care. It's easy to get unlucky here, so save before you try. Once you have the Ribbons, you need to decide who to give them to. Rosa should definitely get one, as your healer is the most important person to keep alive. I'd suggest giving the other to Edge rather than Rydia, so Rydia can benefit from the Wisdom bonus from the Tiara.
The middle cavern holds the Holy Lance, guarded by Plague. This guy is basically a Veteran on steroids. He will cast Doom on your entire party, giving you a ridiculously short time in which to kill him. Bust out the most powerful attacks you have—this is like fighting Odin, only he has more HP and no easily exploitable weakness. Throw Fuma Shuriken at him, summon Bahamut, have Rosa wearing the Minerva Armor firing Artemis Arrows, do whatever you have to. It won't be easy.
The east cavern holds a pair of Ribbons, guarded by a pair of Lunasaurs. These guys will cast Wall on themselves and bounce extremely powerful Bio Spells onto the party. The Walls make it difficult to concentrate on one or the other with Spells, but Baham doesn't care. It's easy to get unlucky here, so save before you try. Once you have the Ribbons, you need to decide who to give them to. Rosa should definitely get one, as your healer is the most important person to keep alive. I'd suggest giving the other to Edge rather than Rydia, so Rydia can benefit from the Wisdom bonus from the Tiara.