Elements doesn't have a single card that directly reduces a creature's attack.(Unless you count antimatter)
Is this intentional? And how would you balance such a card if it existed?
Not sure if intentional, really. I can't imagine that Zanz had a reason not to have one, probably just didn't cross his mind.
I would balance it off
. Seeing as how they cost 8 | 6, I would immediately think to balance it to 4 | 3, since it's reducing half the amount of attack on a target that Antimatter would. However, then I realize that this new card would not heal, and drop it to 3 | 2. I would probably give it to a CC-less element, like Light.