Hearthstone (formerly known as Hearthstone: 'Heroes of Warcraft') is an online collectible card game created by Blizzard Entertainment. It is centered in the universe of Warcraft, and is free download, although with optional purchases to accelerate the pace of card collection and access to extra content.
The game was announced on March 22, 2013, however, during the PAX East 2013 a demo was released.1 2 It was officially released on March 11, 2014. It is currently available for Windows, OS X and iOS mobile devices and Android. In addition to the initial card collection (Basic and Classic), Hearthstone regularly introduces expansions (Goblins vs. Gnomes, The Great Tournament, Whispers of the Ancient Gods, Gadgetzan Mafias, Journey to Un'Goro, Knights of the Frozen Throne, and the most recent: Kobolds & Catacombs) and adventures (The Curse of Naxxramas, Blackrock Mountain, The Expeditionary League and One Night in Kharazan) with new cards and mechanics.
At the beginning of May 2015 the 30 million accounts registered in Hearthstone were reached.3