Final Fantasy V Advance Cheats

Bestiary
Perform the task and you will be able to choose this under "Bestiary" on the main menu. This will allow you to see the facts about the enemies you have defeated. Save game after defeating at least one enemy.

Extra content
The GBA release of FF5 has some extra job classes and dungeons thrown in that are unavailable in previous releases of the game. Getting to all of it is detailed in the following chart.

??? Cave: Available once you get all 12 legendary weapons from Kuza Castle.
Cannoneer, Gladiator, and Oracle jobs: Available when you first enter the ??? Cave.
Cloister of the Dead: Available once you earn the Necromancer job.
Necromancer job: Defeat Enuo in the Sealed Temple.
Sealed Temple: Beat the game once.

Music Player
Beat the game once, then the music player will be available in Extra at the main menu.

Glitch: Easy Walse Castle Basement Looting Glitch
This works only on the Gameboy Advance version of Final Fantasy V. After so many steps, you are automatically thrust into battle. However, if you quicksave, exit and continue, the step counter is reset. If you take only 5 steps, a few more if you're feeling risky, save and load, you can get all the treasures and get out without encountering a single Jackanapes. Like this, you don't have to run if you are going for the Brave Blade and you do not have to encounter the Jackanapes on your first visit to the castle.