"I don't know how many of you ever played Trading Card Games while growing up. I'm sure most of you did: maybe it was Magic: The Gathering. In all likelihood it was Pokemon. Maybe it was something else entirely. The point is, you know how a trading card game works. Even if you never got into one yourself, you know the gist, don't you?
Buy a basic starter deck to play around, maybe get a feel of the game and the rules. Then buy booster packs, get better cards, trade them around, and build an even better and more powerful deck. It's kind of perfect: modern videogaming distilled to its purest, down to buying a base product, supplementing it with DLC, and the social features."