If you could make any item you wanted

[Namillus]

I'd give weapons slots, like in Diablo.

Units used would be:

Halve/Evasion
When equipped, your weapon will hit an enemy as though its EVP was halved.

Halve/Defense
When equipped, your weapon deals damage to an enemy as though its DFP was halved.

Bypass/All
When equipped, your weapon has a 100% hit chance, and deals damage to an enemy as though their DFP was 0. If Zalure is cast upon that enemy, then that enemy takes damage based on the standard DFP reduction of the level of Zalure they're afflicted by.

EDIT: EDIT2: Oops, it's Ult Falz, isn't it? ^.^;