I was thinking that, as a subatomic particle, (and one that supposedly is responsible for the gravitational force in real life physics), I think a blank card of the element is actually fitting art. Photon does a similar thing, and besides, since the entire background normally isn't seen at all, this, in effect, is the only card that would make use of some art already in the game.
I would like it to be submitted, with the understanding that using the gravity background only was a conscious stylistic decision.
Also, I would like to point out that now there are new things to consider in conjunction with this card.
1) It can now be mitosis'd
2) Catapult strikes me as quite a nice way of killing it
3) Now, sanctuary exists as a sort of shut down for this