Numbers very tentative.

--CF

What's revel do? It's not on the mechanics page.

Same as in set 1 of the block, but I've added them to the mechanics page now that there are more cards here in set 2.

--CF

... And this doesn't actually make any sense, because the mana you get from the damage just cancels out the cost of the ability. Just removing the mana cost means this would have to go to a higher cmc, but could play with activate only N times per turn with no activation cost or just a repeatable trigger to sac things for damage.

--CF

Hmm; this is "Oh, you're on 10 life? Machine gun time!" and you can do it from six mana; and there's not even any warning.

On the plus side; it's nonland only. And if they have a healing salve, you just lost.

This mechanic seems difficult to balance, and better suited to appearing on a few rares.

Well, it's a perfectly sane and safe mechanic on otherwise vanilla creatures. A small mana boost; but on attack rather than on utility; so slightly riskier to use. Price it up like the myr.

But on something that repeatably deals damage? Owie.

Well, it's a faction mechanic right now, so it appears on 10+ commons and uncommons. Certainly hoping that it proves tractable to balance in playtests, but in the worst case we could find a new mechanic for R. This particular card is just silly right now, as noted above -- I kind of doubt that anything with a repeatable damage dealing activated ability and revel will end up happening.

--CF