Change Overworld music

In Chapter V, after you have found all seven chosen ones (Ragnar, Alena, Brey, Cristo, Taloon, Nara, and Mara), you can change the music on the overworld. Place Ragnar at the lead of the party if you want Chapter I music, place Alena, Brey, or Cristo for Chapter II music, Taloon for Chapter III, Nara or Mara for Chapter IV, and the Hero for all-new music. If you want the Hero's old music, set him/her at the head of the party with no one else in it.

Metal Babble Sword

Chp. 5, only after you get the Final Key.

Between Aktemto and Santeem (North to South), there is a town called Seaside Village. Go there at night. Go to the lower left corner of the town and note the small patch of sand in the water. Go back during the day, and search the spot. You'll find the Stone of Drought. From the Seaside Village, get in your ship and go North, then West when possible. You should eventually see land. Go onto the land and you should see a cave. In the cave, north. At the wall, you'll see a tile of water which looks a little different. Use the Stone of Drought right there. Once inside, just unlock the various doors, and wrok your way down several floors. On the bottom floor (4th floor), you'll find the Metal Babble Sword. Along with being the strongest sword in the Game, it garuntees a hit on Metal creatures.

Always inflict critical hits in boss battles (Japanese version only)

This weird glitch only works in the Japanese version of the game. When you're fighting any boss, choose to escape 8 times. Each time will fail, but if you do this procedure, for the remainder of the battle your physical attacks will always be critical hits! It doesn't matter what you do in between the failed escape attempts; you ARE allowed to do other things (such as cast spells) in between each escape attempt, but be sure you can survive getting attacked freely for each escape attempt.