Hearthstone's Fourth Button Mystery Revealed: New PvP Mode Coming

The mystery of the fourth button has been revealed: Hearthstone is introducing a new mode called Tavern Brawl in the upcoming 2.7 patch.

This new player-versus-player mode consists of games played with a unique set of rules that change every week. Blizzard suggested possibilities like playing with preset decks, newly built decks that must follow certain guidelines, or with certain minion types being buffed. You'll be able to take part in these matches against random players online or against friends by challenging them from your friends list. Either way, you'll be able to play for free.

Tavern Brawl will be added in a patch "coming soon," but it won't be available for all players straight out of the gate. In order to access it, you'll first need to reach level 20 with at least one hero.

After the end of each Tavern Brawl, there will be a "couple of days" when they are unavailable as Blizzard prepares the next one.

Blizzard wasn't especially specific about when patch 2.7 will be released, but it did say the first Tavern Brawl will be here in "mid-June," meaning it could be out any day now. Once the mode arrives, you'll be able to win a free card pack each time you win your first game of the week during "the first several brawls."

This patch will also introduce the first new heroes, as recently announced. These cosmetic-only packs cost $10 each and don't change gameplay in any way. Instead, they replace the look and sound of select heroes. Additionally, with the release of the new patch, you'll be able to assign a different card back to each of your decks.