Mognet Central
Closer to the end of disc three, something will start to go wrong with Mognet, the Moogle's way of delivering mail to one another. In order to fix it, you must locate several moogles, and deliver mail amoung them. You must find them in this order:
1. Get the first letter from Kupo, at Alexandria bell tower. Deliver his mail to Atla
2. Atla is the moogle in Burmecia, in the area before you fought Beatrix. After delivering the mail from Kupo, get a letter from her, and take it to Mogryo.
3. Mogryo is the moogle at the waterfall in the Black Mage Village. Give him the letter, then get one for Kumool.
4. Kumool is the first moogle in Ipsen's castle, in that room where the fllor trap's opened up. Give him the letter from Mogryo, then get one for Mois.
5. Mois is the moogle at the entrance to Fossil Roo, which you enter through Qu's Marsh. After delivering him the mail, get the mail for Noggy.
6. Noggy is located at Daguerro. You find her on that top ledge, right beside the pit with the four armed man(who tells you your rank, his name is actually Gilgamesh, like the gf from ff8). Give Noggy the mail, then get a letter for Kupo.
7. Go back to the Alexandria bell tower and deliver the mail, to find out that you need to find the superslick to make Mognet run again.
Go to Ruby's minitheater and talk to her. It turns out she used Superslick in her hair, but gives it to Zidane. Go to Mognet Central and give Artemicion the superslick. He'll give you a protect ring for your efforts. The Machines will operate once more and Stiltzkin will show up. Mosh will then tell you how many letters you delievered. And there you go, Mognet is fixed!!
Ozma
Unlike ff8's Omega weapon, this battle is about 95% luck. Basically you have to depend what kind of mood Ozma's in to beat him. To find him, go to the Chocobo's airgarden, and go to the left island. Look at the tomb-looking thing, and Mene will say about terrible force. You will get one last chance to switch party members, open menu, etc. Choose ready to fight him.
His attacks:
Lv 5 Death-casts death on all party members whose level is a multiple of 5
Lv 4 Holy-casts holy on all party members whose level is a multiple of 4
Death-casts death on a single party member(most people have a problem with this, but it always missed for me when he used it)
Holy-casts holy on a single party member
Doomsday-does major shadow damage to everyone, sometimes including Ozma
Meteor-another heavy hitter, doing anywhere from 300-9999to everyone.
Curse-does around 4000+hp and causes lots of status ailments
How I beat him:
It took me about 10 tries to beat Ozma. My party consisted of the people that no one would dare use against him. It was Zidane-level 94, Dagger-level 86, Vivi-level 86, and Quina-level 86. I equipped eqoist's armlet to reduce shadow damage(doomsday) by 100%, and had the highest weapon's for the rest. Abilities I had equipped on everyone were auto-life, auto-haste, auto-regen, level up and ability up. I had over 200 frogs with Quina, making his frog drop do 9999 everytime. I also had Ark.
How I won: Things went pretty smoothly in the final battle. I had Zidane, Dagger, and Vivi all healing, while I hacked away at Ozma with frog drop. He killed Quina, but auto-life restored him. When he used curse, it didn't kill everyone, but did serious damage. I quickly healed everyone and continued the frog drop assault. When all my guys were at full health, Zidane hit trance, so i used Quina's frog drop(9999), Zidane's grand lethal(9999), Dagger's Ark summon(6000+), and Vivi's flare(6000+). He used curse again and killed my party, but auto-life restored them, and killed the status problems. I used life on Quina, then used frog drop and grand lethal a couple more times and beat him. For beating Ozma, you get 2 Ozma cards, a strategy guide(which I still don't know what it does), and a Pumice(which if you don't have Ark yet, you can use to get him).