Diablo III hit shelves at midnight at more than 8,000 stores across the world, including HMV's Oxford Street branch.
The long-awaited PC and Mac RPG arrived with more than 2m pre-orders, which includes both retail and digital purchases.
Fans were queuing at HMV Oxford Street in London as early as Saturday.There were also game developers on hand to sign copies of the game for early customers.
Diablo III is available at retail in the UK, US, Canada, Europe, South Korea, Southeast Asia, Australia, New Zealand, and the regions of Taiwan, Hong Kong and Macau. It's also available to download online.
The game has experienced server troubles at launch, with many players online reporting an 'Error 37' login problem.
This launch is a culmination of many years of hard work by our development team, and many years of passionate, dedicated support from gamers around the world,” said Blizzard Entertainment CEO and co-founder Mike Morhaime.
We're grateful for the enthusiasm of our players, and for the help of our beta testers in getting the game ready for release. Now that Diablo III is live, we hope everyone's ready to have a hellishly good time slaying demons and collecting loot in Sanctuary.”