Kingdom Hearts II need help on 2 visit to agrabah (or something like that)

When i was playing kh1 i decided to drop in at agraba (that place where aladin lives) and apon landing the ship i was attact by this huge creature! i charged at it and fought for a bit.Then my attacts started doing no damage at all! before i could try something else it beat me. then for a few hours it was rinse and repeat. any suggestions?

 

It's called Kurt Zisa and it's a extra boss.
When you begin the battle,you can't use magics and you need to break some "balls" that are on his hand,be sure to have good items(Elixirs on Sora,Mega-Potion and Mega-Ether on Donald and Goofy) and/or a high level because you can't use Cure.
After you defeat the balls you will be able to use magics again, and a snake thing will appear(The snake is the boss itself)hit it as much as you can because after some time he will recover.
Now he has a Large Balll around him and normal attacks don't hurt it,so use magics and summons (I like to use Dumbo or Mushu) and keep attacking it until the ball is gone and the "snake" appear again.
After he recovers he will start everything from the beginning,he will seal your magics and four balls will appear.
Repeat everything you did until now to beat it.