With the extremely successful single-player-focused Curse of Naxxramas add-on now behind them, Hearthstone: Heroes of Warcraft developer Blizzard has revealed that the collectible card game's first expansion will further expand on the card pool, but also add new strategies and a common theme like the aforementioned add-on.

Speaking with Polygon, Hearthstone production director Jason Chayes offered some early details about the future of the game. "I think we're going to mix it up a little bit with this next release, which will be our first expansion," Chayes said. "It will have a lot more cards. We're talking about more than 100. We are going to have a central theme for how that will all fit together. That'll be the next thing coming up."

The team are also looking at how to further improve on the game's pacing, not just for seasoned veterans but also those new to the free-to-play collectible card game. "We really want to pay attention to how that is for the entirety of the player base. Does that feel like the right amount of content? Is it too little? Is it too much? We feel like this is a good starting point."

There’s no time frame for the next major content update right now. For more on Hearthstone’s future, check out the interview at Polygon.