A teaser page on Diablo III’s official site suggests an expansion called Reaper of Souls is on the way.
The page shows a dark passageway along with a quote from the Book of Tyrael, which reads "Death, at last, shall spread its wings over all".
Text at the bottom of the page indicates that Reaper of Souls has been trademarked by Blizzard.
Blizzard President Michael Morhaime recently said the company would share "Diablo-related news” at Gamescom.
Meanwhile, Diablo III is due to arrive on Xbox 360 and PlayStation 3 on September 3, and PlayStation 4 sometime next year.