Ys: the Vanished Omens Cheats
for Master System

Final Boss Hint

For best results, unequip the Battle Gear and Flame Sword and use the Silver Equipment. If you doubt the strength of Silver, consider why anything Silver has been stolen or bought in the beginning. The Silver will do more damage and decrease damage taken from the Final Boss.

Get More Money

When you start a new game, go to the only shop that is selling a ring. It is towards the lower left. Buy this ring then go to one of the houses near the top right of the town. Talk to, I think the third guy in the room and he offers you one and a half times of the amount of gold you paid for it.
Later when you go to the very bottom right corner of the grasslands, there is a big lake you should search the shores of. You will find some artifact you can sell.