Hearthstone is a 20 million-player game of cards

Hearthstone: Heroes of Warcraft has dealt in 20 million players around the world, the game's official Twitter account announced today. The tweet reads, "Thank you all for joining us in #Hearthstone! We're going to need a bigger tavern!"

Hearthstone is Blizzard's free, strategy card game based on Warcraft lore for PC, Mac, iPad and Windows 8 Touch devices. Android and iPhone versions of the game are due out before the end of the year, Lead Designer Eric Dodds told Joystiq at PAX Prime.

[Image: Blizzard]