Following this declaration, Rob Pardo, an executive at Blizzard - the firm behind Diablo 3 and World of Warcraft - said that Windows 8 was "not awesome for Blizzard either".

BBC: Minecraft screenshot

Cards in the game are based around characters, spells and artefacts from Blizzard's Warcraft world to make them immediately familiar to players, said Rob Pardo, Blizzard chief executive during a presentation about Hearthstone at the Pax East gaming convention.

BBC: Blizzard reveals Warcraft-themed card game