XBOX's top performing studio has been reportedly 'revealed' after an internal memo is claimed to have been obtained and verified. Windows Central reports it obtained a leaked internal email from Blizzard Entertainment, the makers of Overwatch, Diablo and World of Warcraft, which it verified saying Blizzard is the top performing studio owned by XBOX. Blizzard is no longer part of Activision and is its own studio within the XBOX gaming division. And the email, reportedly sent by Blizzard president Johanna Faries, revealed Blizzard had a strong Fiscal Year and returned to growth despite XBOX going down by 11 per cent. Neither Blizzard or XBOX have officially confirmed this internal email at the time of writing.