Blizzard Entertainment has officially announced that they have begun closed beta-testing of their upcoming World of Warcraft expansion: Cataclysm. The expansion will launch later this year and will feature a complete overhaul of much of the game’s existing maps via phasing technology in which higher-level players will see the world in an entirely different state than lower-level ones. Invitations to this test are randomly going out to those who registered their Battle NET accounts with the opt-in for beta test programs.

‘Our focus with Cataclysm has been to build on the knowledge we’ve gained through the previous expansions to deliver the best, most compelling World of Warcraft content for our players to date,’ said Mike Morhaime, CEO and cofounder of Blizzard Entertainment. ‘Gathering focused feedback during the beta test will go a long way in helping us reach that goal when we launch Cataclysm later this year.’

World of Warcraft: Cataclysm will focus on a the apocalyptic return of Deathwing to the world of Azeroth.