Nope. Sorry, Mojang. $20 (apparently a discounted
price??!) is still too much for this and I won't bite.
Now Minecraft, on the other hand? Best $20 I've ever
spent on a game, but that was different. I had a huuuuuge, sprawling virtual world to explore, live in and build things in with my friends/family, where the possibilities are virtually limitless. The epic, amazing times we've shared in that game (and still share) made that a very special experience in my book, worth whatever price would have been charged.
But this is just a digital card game, man. Come on.