The third World of Warcraft expansion, Cataclysm, is the world's fastest-selling PC game.
In 24 hours Cataclysm sold 3.3 million copies worldwide, on Mac and PC.
Compare that to the world's fastest selling multi-platform game Call of Duty: Black Ops, which sold 5.7 million copies in 24 hours, and Blizzard's achievement speaks for itself.
The second World of Warcraft expansion, Wrath of the Lich King, had been the world's fastest selling PC game with a day-one tally of 2.8 million sales.
A staggering simultaneous worldwide launch for Cataclysm helped Blizzard make the record possible. Cataclysm hit shelves in United States, Canada, Mexico, Argentina, Chile, Europe, Russia, Southeast Asia, Australia, and New Zealand on 7th December, and then in Korea and the regions of Taiwan, Hong Kong, and Macau on 9th December.
"We had to bring Azeroth to the brink of destruction in Cataclysm, but the result was our best expansion yet," commented Mike Morhaime, the man who made Blizzard.
"We want to thank all of our new, existing, and returning players throughout the world for their incredible enthusiasm and support, and we look forward to hearing what they think about all the new content."
Will the next World of Warcraft expansion, said to be smaller and therefore quicker to develop, repeat the cycle and smash Cataclysm's record?
More pertinently, what on earth can topple World of Warcraft? Eurogamer asked Blizzard peers and analysts the very same question to make for some intriguing results.