Tom Chilton headed Blizzard’s World of Warcraft for 13 years. For two years, he’s been leading a super secret project that is drastically different from anything Blizzard has ever done.

Speaking with GamesBeat, J. Allen Brack, Blizzard Entertainment’s new president, told Dean Takahashi that Chilton is working on a passion project. From the sounds of it, this project has been in the works for a very long time. “He and I started up a new project that was not something like Blizzard has ever done before.”