If you give it to your opponent, wouldn't it be a good thing if they played it? Unless you spam the crap out of lightning, hm.
It depends on what creatures you have in play.
I.e. if you have only mind worms and voodoo dolls in play, they're just asking for trouble by playing it...
Plus, they have to be using a
deck or they will be ****ed
You can really mess with em if you use nightmare, this, and silence