If you haven't heard of it, well I should smack you.
Its basically a game where someone took Magic: The gathering and combined it with and RTS.
The gameplay is basic and actually pretty easy to learn. There are 4 different basic type of cards.
Fire, Frost, Nature, and Shadow, then you got your cards that share elements like fire and shadow and frost and nature.
To play a card you need a certain amount of energy gathered and 1-4 orbs.
Go here http://www.battleforge.com/portal/site/BattleForge/tutorials/
provides a better explanation of the game.
Also best of all its F2P though I should tell you that honestly I suggest spending 30 bucks on it.
While the F2P gives you free 30 cards to start out with, spending 30 bucks give you 4 decks of each element type and 3000 points to spend on booster packs.