Why the Apple of gaming went from World of Warcraft to iPhone games

Blizzard gained many fans with its seminal MMORPG - but it's the virtual card game Hearthstone that's making it a household name

One of the striking things about Blizzard, the superstar developer behind some of gaming's biggest hits, including World of Warcraft, Diablo and Starcraft, is how little it actually does.

That's not to say the company's employees aren't constantly at work, although the Kendo lessons taking place on the lawn outside its headquarters in Irvine, California, on the sunny spring day I visit could give that impression.