I wish I had written this (Fletch, remember when you wanted a good idea? This was it...). A cross between Magic: the Gathering and D&D, with a very 1980's vibe. It's cute, fun, funny, and even a little bit challenging. And it's free!
I spent $10 because the designers deserved to get paid. This game is everything Flash games promised to be (it's played entirely from a browser) but aren't (Cardhunters is a real game, not a simple pig-throwing exercise with a single dimension of freedom). For my ten bucks I got the 11 bonus missions, which means I can play the whole game for free. The only thing more money gets you is more loot faster, but the game is very well balanced. Just because an item is higher level and rarer doesn't mean you'll want to use it; and the difference between items is pretty small.
You play a D&D player, playing a D&D party, while Gary (and his older brother Melvin) entertain you with their differing ideas on the art of Dungeon-mastering. The whole thing is a pitch-perfect sendup of my D&D youth.