Blizzard has said that the World of Warcraft's second expansion pack, Wrath of the Lich King, has sold more than 2.8 million copies in its first day on sale.
Its performance has earnt the game the title of fastest-selling PC game of all time, eclipsing the record of 2.4 million previously set last year by the first World of Warcraft expansion, The Burning Crusade.
The game was always set to be a huge hit, with more than 15,000 stores across the world choosing to open their doors at midnight for fans to get their hands on the game as soon as possible.
"We're grateful for the incredible support that players around the world have continued to show for World of Warcraft," said Mike Morhaime, CEO and cofounder of Blizzard Entertainment.
"Wrath of the Lich King contains some of the best content we’ve created for the game so far, and we look forward to seeing even more players log in to experience it in the days ahead."