This seems a little underwhelming because it is, but sacrificing things as part of a cost really isn't that difficult to get going in Grixis
It has Fighting resistance -30: it takes 30 less damage from attacks made by Fighting type Pokmon
However, I cannot ignore a couple of noteworthy, valuable oversized cards that came out this millennium
Decks like these could easily find a home for Airbender Ascension, and may even be able to blink or cast enough creatures to get its second ability going
If that creature is a legal target but the other creature isn't, you'll still put the +1/+1 counter on the creature you control, but neither creature will deal or be dealt damage
Well, expect even more of a frenzy over collecting them all when the next set, currently known as A2, drops