So... do you have to waste a quicken on this or what? I don't get it. You can only cast this spell on a turn when you can't cast it :S ?

EDIT: Nevermind, on the main page for it, it is listed as an instant. It deserves better than a 3.5/5 then. It does cost more than a fog, but it's way better than one, as you can still tear them apart. Will rate 4.5.