Divine Transformation

A rare aura! I bet it's amazing! Let's see ... +3/+3, not bad.  Flying, OK. ... That's it?

Note how all these others are literally terrifying. Note how they completely change the game if they resolve. Celestial Mantle turns races into jokes; Footsteps replaces itself in one turn; Splinter Twin literally wins the game now; Bear Umbra doubles your mana; Eldrazi Conscription literally wins the game in a turn or two. (It's a little worse than Splinter Twin.)

Divine Transformation turns your Benalish Hero into a four-more-turns clock, unless the opponent has a Swords to Plowshares. Or a Lightning Bolt. Or a Hurricane. Or a Darkblast. Or an Engineered Explosives. Or a Lava Dart. Or a Lava Dart in the 'yard with a Mountain in play.

Sure, the same's true of the other auras -- but they have a much, much bigger impact on the board. If you don't have that Darkblast, these other auras will all eat you for lunch. Divine Transformation? Not so much. It's not even that great on a big guy. If you'll recall the Craw Wurm discussion, power scales very poorly. That means this card shines most on a small guy, where you're cutting clocks from 20 or 10 turns to 5 or 4 turns; on a 5/5, you cut the clock from four turns to 3 turns. Hooray?

The upside just isn't worth it. If Lava Spike isn't generally playable, then this card isn't -- they're essentially the same thing, with this card requiring more mana and a creature, with the strong downside of being blank to removal, not just counterspells

In every other incarnation, this card's been at uncommon, where it's a limited beater -- and make no mistake, this card ruins days in limited -- but it's just so far behind the curve in every other way. Still, it could be printed at uncommon today, where it'd be a crowd-pleaser with the uber-casuals; I like to think, however, that the set most obsessed with auras would have a few playable auras at rare.

This probably wouldn't crack any Standard tourneys, but it's cool, it replaces itself (like Griffin Guide made of ladies) and is actually good enough that I could see it in a semi-serious deck. It's a nice Wrath protection in EDH, where you can invest heavily into the board and have an aggro Caller of the Claw that you don't need to hang on to. White's not a huge hexproof player, but blue and green are -- and there's more than a few generals in those color combinations.