The website quotes Book of Tyrell "Death, at last, shall spread its wings over all" across a depiction of a dark, foreboding doorway.
Blizzard is expected to reveal more about its Diablo franchise during Gamescom 2013, with Mike Morhaime, Blizzard president and co-founder, stating that the company will "be sharing more Diablo-related news at Gamescom later this month." It will host a press briefing on the first day of the event on Aug. 21, where it will make "a special announcement that's sure to capture the attention of the Heavens, Burning Hells and all the shadowed places that lie between."
Last November, Morhaime stated Blizzard does have expansion plans for Diablo 3 but no timeframe to talk about it, saying the quality of the expansion will drive its schedule. Blizzard released Diablo 3 on Windows PC and Mac last year. It plans to launch the title on PlayStation 3 and Xbox 360 on Sept. 3, with a PlayStation 4 release expected in 2014.
We have reached out to Blizzard for more information.