I can't remember how do we get the Curse Shield.
Who remembers?

Equip the Crused Shield on one of your characters and you have to win 255 battles with it equipped. Also, you should have the "Ribbon" accessory on whoever has teh Crused Shield because while wearing the shield, you are inflicted with many status effects. The Ribbon removes all of them except the Doom spell.

Its in one of the locked houses in Narshe in the WoR, so you need Locke to get to it. An old man gives it to you, then do as Bustamo said to morph it into the 'Paladin Sheild'.

Ok about the Pally shield, in the PS version it says it gives you Ultima x1. Is that true?

Yes, it has the ability to learn your characters Ultima at a rate of 1% per AP just like the Ragnarok Esper. Thats why if you plan on getting the Paladin Sheild (highly recommended, it IS the BEST sheild in the entire game) then its best to change the Magicite into the sword when given the chance in Narshe. That way you get Ragnarok the sword (powerfull!), bet it for the Illumina-Lightbringer (an even better sword than the Ragnarok!), AND still be able to learn Ultima!

Yeah, like Moonchild said.
That's may idea. And the best way to break the curse is in the Solitary Island and fight those Peppers, they only have 1 or 2 HP and even if you don't attack they'll dye.

One more thing... Is Illumina-Lightbringer still the most powerful weapon in the game?

And I remember a time that I had many, but many Illuminas (about 200 or something). Those were nice times... P.S.: I had all of them in the WoB. Hehehehehehehehehehehehehehehehehehehehehehehehehe hehehehehehe.

Sketched it right up I take it

I think the Lightbringer is still the most powerfull, Its certainly my best so far. But I used the all items cheat one time to check stuff out, as you do, and theres quite afew nifty weapons about but never took the time to check if they were actually better or not.

I just bagged my Cursed Sheild, heading off to the Island now

Yeah I have been fighting with my Cursed Shield equipped for quite some time now, well into the hundreds for battles, but I have yet to see the transformation. I started keeping a sheet of paper and tally marking all my battle victories, but forgot to keep marking them down after the 150th or so.

Guess you'll know when the little numbers above your characters head stop showing up in battle.

Poor Locke, he'll never want to see the number 42 ever again....

It gives ultima in the snes and gba versions too and i always get the shield in every game i go through