Blizzard has been keeping its players well updated about the upcoming expansion for Hearthstone: Heroes of Warcraft, Goblins vs. Gnomes, and now they're letting you play the cards before they're even released.

Right now in Hearthstone's arena mode, Goblins and Gnomes are running rampant waiting for a hero to control them -- that hero could be you. Polygon reports that although the official release for the Goblins vs. Gnomes expansion pack isn't until next week, "players worldwide can hop into the game's Arena right now to take them for a test run."

Not only do you get a sneak peak at the all new expansion pack, but if you log in before Dec. 8, you also get a key for the arena, completely free.

"It's a zero-risk chance to see some of the new cards in action--with a high-risk chance of something going explosively awry," said a Blizzard representative. "And if you're already in the middle of an epic Arena run that won't be finished before December 8, don't worry -- just make sure to log in during the pre-launch period, and you'll be good to go."

If you want to permanently play this expansion, be ready to duel on Dec. 8 in North America.