Ys I & II Chronicles, Vampire Boss (spoilers)

So, I got the game, at first it wasn't too great since you can't use your sword freely, but I got over it and started enjoying the game

Now I'm at the vampire boss and it's too damn hard, I'm starting to get frustrated cause I cannot level up past level 10, I mean WTF, anyone knows if I need a special item or something to beat him, already got four rings (atk, def, slow, recovery), silver armor, silver shield, Talwar Sword.

Maybe a better sword, but I have no idea where to get it.

Any help would be appreciated

A manual comes with both the digital and UMD version of the game that contains a good walkthrough that will help you out here. It's at the back of the manual.

Like the booklet says (cough), you need the silver sword to really do any damage.