Final Fantasy III Cheats

Back in the original Famicom FFIII, Onion Swordsman was the first job you start as (unlike Freelance from the DS version), but you can play this job in the Nintendo DS version as well by unlocking it. Onion Swordsman is one of the most powerful jobs with the Onion Equipment + past level 90's.

How to obtain:
1)Register someone elses's (or multiple) communication ID under Mog Net.
2)Send message to another PC 7 times
3)Send and receive 4 messages from Topapa, on the fourth one you will receive a message to do a mini-quest.
4)Go to Ur (First town in the game)
5)Talk to Topapa
6)Go to the cave up north of the cave
7)At the drop hole, you will have an event and then will be proceeded to fight 3 bombs
8)After the battle, you will obtain a piece of crystal, which will unlock Onion Swordsman

In the Nintendo DS version of FFIII, there is a secret dungeon that contains a secret boss harder than the last boss, in order to obtain access:

1)Send a total 7 mails to another PC (one or multiple) using Mog Net.
2)Send 4 mails using Mog Net to the NPC: The 4 Elderly
3)Send 4 mails to King Arusu and after reading the fourth one, you'll unlock a quest
4)Go ride on the airship that can go underwater
5)Head for the floating island and once finding it, go exactly east..
6)You will eventually see a shadow in the waters, once you do go underwater to enter the cave
7)Soon after entering the dungeon, you will meet the secret boss

*This boss is notorious and mean. It does a total of 4 attacks per sound and also uses Meteo. Please be at a very high level before attempting this fight.