Blizzard isn’t releasing the next expansion for its online card battler until next week, but it’s letting you mess around with some of the cards right now.

All 120 new cards that are coming Monday in the Goblins vs. Gnomes expansion for Hearthstone are now available in its Arena mode. This is the draft that costs real-money or in-game gold to participate in, and it lets you build a temporary deck that you lose access to as soon as you lose three matches. This move gives you a chance to see how some of the cards work before plunking down the cash to buy them next week. Hearthstone is in the top 100 highest-grossing apps on iPad, but it has fallen off the download charts completely, and this add-on should give it a bump.

To encourage you to check out the cards in Arena, Blizzard is also making everyone’s next run between Dec. 4 and Dec. 8 free. As long as you log in to the game during that time, you’re next run is free even if you start it after Dec. 8.

Hearthstone is Blizzard’s first big push into free-to-play gaming, and Goblins vs. Gnomes is only the game’s first big expansion. Unlike the Curse of Naxxramas add-on, which focused on single-player content, this add-on is all about introducing new cards and strategies. The developer will likely wait to see how this new content performs to help it decide how to handle expansions in the future.

Check out some of the Goblins vs. Gnomes cards below: