Get a lot of experience points and money
  At the very first town there is a house in the back that has a chimney. You
  can go straight through it and find a computer. When you use it, it will start
  a battle. At the end of the battle you will receive a ton of experience points
  and money.

Secret room in Chaos Castle
  In Chaos Castle, there are escalators in front of you. Take the only one going
  up at your left. While going up, hold right. You'll go into a secret room with
  a chest with a Elixer in it.


Hints by Felipe Gerhard - felipe.gerhard@gmx.net