I loathe confusion. I learned to FEAR it from playing the final battle in Legend of Dragoon.

Final Fantasy cuts you a bigger break with confusion in that once you get physically hit it wears off, but it is still something to be feared.

It's like sleep, but only worse. You can't control your characters like sleep, but unlike sleep, you're getting beaten to hell with your own guys.

That said, confusion isn't the worst. It's condemn.

I say condemn and not heat from FFIX because often times condemn is cast on the entire party making it truly terrible.