The unofficial mod is a new adventure inspired by, and set in the world of, Hexen. The demo version contains the Cleric's first hub, with three maps and an estimated 1.5 to 2 hours of monster-slaying and puzzle-solving gameplay.
The original Hexen was released in 1995 as a sequel to 1994's Heretic, built upon id Software's Doom engine. Hexen 2 followed in 1997. The last entry in the series, 1998's Heretic 2, was something of a departure from the norm, set a thousand years after Hexen 2 and featuring a third-person perspective.