Good idea in general, but
is the wrong element for it mechanically, as
already has Momentum.
When Wings is going to be the only card that affects non-Airborne creatures, then your are right. But I hope that zanz doesn't create the Airborne-ability only to use it for one shield.

And the two other elements with only 1 Airborne creatures are
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and

. But Water doesn't throw something in the air. I could used Earth but I think that Earth doesn't provide enough power to throw a heavy creature high enough.
No, I think Gravity is the best element for this idea.
