It's true - the world is big into Diablo 3 . So much so that the game was purchased more than 3.5 million times in its first 24 hours available, making it the "fastest-selling PC game" of all time, according to Blizzard. On top of that 3.5 million, another 1.2 million copies were scooped via the WoW Annual Pass (which included a free copy of D3 ).