Great digital collectible card game. Fast to learn, a lifetime to master. Much different than Magic: The Gathering but IMHO just as fun. The strictly digital nature of the game (it has no printed equivalent) means the rules on cards can be buffed or nerfed or otherwise changed in order to address game balance changes or to reflect storyline changes resulting from events, etc. Also, you'll be tempted to buy cards at first (especially to et new warlords or certain rares) but if you play long enough, you'll earn enough in-game currency to spend on cards; basically, the game is free and, if you're talented and lucky, you can be quite competitive in short order.