Reminds me of Chant of Vitu-Ghazi. I don't think I've seen "Draw cards equal to the damage prevented this way" before, though. Interesting.

That will inevitably be a massive number of cards. 10 or 20 cards if you block your opponent's fatties with your own.

The funny thing about this card is that it's so aggressive. If you're playing correctly, you should play it when you're attacking. Man, your opponent will be ticked if he decides to block...

You could probably argue this should be green. White doesn't really get mass card-draw at all, but green gets it if it's tied to creatures, especially creatures' power. And Fog effects have bouced between white and green several times, and happen to be back in green at the moment.

I'm not that worried about aggressive decks using this early, because twelve total mana and cards in graveyard is enough that you won't hit it very early. Unless you're playing some strange "self-mill / aggro" deck. Um, like Dredge, I guess.

I was thinking more mid-range, but aggro, spending a lot of early rounds tossing Rampant Growths into the graveyard, dropping a pile of creatures on rounds 4 and 5, then swinging to intentionally prevent a pile of damage in a clogged board state, then drawing a pile of cards. That being said, I'm not really afraid of that deck either. The whole process can be done in a much simpler fashion with Greater Good.