Both rumors are based on job listings at Blizzard, one of which no longer exists.
The listing that vanished called for a developer to help work on "restoring" Warcraft 3 and Diablo 2 to their former 'glory.' What's interesting about this job listing, caught by Blizzplanet, is that the wording is nearly identical to a job listing that appeared two years prior – only with slight changes.
Compelling stories. Intense multiplayer. Endless replayability. Qualities that made StarCraft, Warcraft III, and Diablo II the titans of their day. Evolving operating systems, hardware, and online services have made them more difficult to be experienced by their loyal followers or reaching a new generation.
We’re restoring them to glory, and we need your engineering talents, your passion, and your ability to get tough jobs done.
If you like wearing many hats, know small teams are the most effective, and look forward to challenges that will create millions of new adventures for our players, we would love to hear from you.
The listing mentions StarCraft, which has already been worked on and released as free-to-play. As for Warcraft 3, Blizzard made the game compatible with Windows 10 last year as part of Blizzard's first move in a bigger scheme.
While this listing is gone, there are other listings that call for classic game remasters.
The other posts that continue to exist are for an 'unannounced project' which calls for a Production Director for the Diablo franchise, as well as a Senior Game Producer, Senior Level Designer and Creative Director (via Gaf).
The Production Director post makes it sound like a new game is in the works:
"Blizzard Entertainment is seeking a Production Director to bring the Diablo franchise into the future. We’re looking for a well-practiced producer, deeply familiar with the art of game development, our industry, and the AAA environment."
The details for the position include MMO experience, which suggests Diablo 4 will feature some MMO features. It's unclear how extensive the MMO themes will play into Diablo 4 (if the listing is indeed for Diablo 4).
- A passion/interest for developing online video games
- Massive multiplayer game development experience
- Strong knowledge of the software / game market and platforms
The Creative Director listing mentions the 'future' of the Diablo franchise, which kind of confirms Diablo 4.
Blizzard Entertainment is looking for a seasoned creative director to join our Diablo team as we look to the future! The ideal candidate will understand the core of what makes the Diablo universe resonate with players, and will be able to collaborate with art and design to rally around a consistent vision of world, story, and tone.