Hearthstone's next add-on will be a full expansion with over 100 new cards

Hearthstone players have largely praised the free-to-play card game's recent single-player-focused Curse of Naxxramas content, but any fan of collectible card games knows that the genre thrives off of a steady flow of new cards to learn and master. Blizzard is aware of this as well and has big plans in place for what's next with the game.

Speaking to Polygon, Hearthstone production director Jason Chayes revealed some early details on what's coming next.

"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."

"One of the things that we spend a lot of time talking about is pacing," said Chayes. "Not just the pacing of the game as it is, but pacing of the rollout of new content. We really want to make sure the pacing is great not just for seasoned Hearthstone players but for new players coming into the game too.

"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."

Hearthstone's first add-on, Curse of Naxxramas, started rolling out in July, with a new "wing" of bosses and cards released every week for five weeks. In total, Curse of Naxxramas added 30 new cards to the game plus some tough single-player challenges.

"It will have a lot more cards. We're talking about more than 100."

According to Chayes, Blizzard is very happy with how the Naxxramas content turned out.

"We didn't really know how it was going to go," he said. "We were excited about the idea of having not just a singular event. It wasn't, 'All the cards are out, everybody go and try to wrap your heads around all those new cards in one shot.' It was a gradual rollout. We had this vision of having this month-long celebration, and that actually worked out great."

While Blizzard's small Hearthstone team is still figuring out the perfect approach to new content, Chayes says that if the upcoming expansion works out well, "we could imagine a future where we do a combination of [single-player] adventures like Naxxramas and expansions kind of intermixed to have different sorts of experiences going out over the course of a year."

As for expanding on Hearthstone's current game types being offered, Chayes says he would like to do that while also building on the modes currently in the game.

"There is the idea to expand and have new modes where players can play in different ways," he said. "That's not something we're looking at super short term. That's something that's a little further out, because we want to keep pushing the modes that are there."

With over 100 new cards on the way, we also asked Chayes if he's at all concerned about Hearthstone hitting the breaking point that other popular card games like Magic: The Gathering have, where there are so many cards available that they've had to limit what is allowed to be played in certain modes at certain times.

"We have done some initial conversations about at what point will that be a concern for us," Chayes said. "We think we have a ways before we have to worry about something like that, because there's a lot of design space to experiment with ideas.... But that could be something that we need to be thinking about for Hearthstone down the road.

"If we do reach that point because there are just that many cards in the available set, one of the things we definitely want to make sure of is that there are ways to continue playing with all of your cards, and that it feels really good to be participating in these various modes."

Chayes couldn't provide specifics on when we'll be seeing more details on the upcoming expansion for Hearthstone, but he did say to expect news "very soon." With Blizzard's yearly BlizzCon event kicking off on Nov. 7, our first look at the new cards certainly could be close.