Pickle released an engine port to be used with Hexen II data files.

Here is some background information for Hexen II, shameless stolen from Wikipedia ( http://en.wikipedia.org/wiki/Hexen_II ):

Hexen II was a first-person shooter computer game developed by Raven Software from 1996 to 1997, published by id Software and distributed by Activision. It was the third game in the Hexen/Heretic series, and the last in the Serpent Riders trilogy. Using a modified Quake engine, it featured single player and multi player game modes, as well as four character classes to choose from, each with different abilities. These included the offensive Paladin, the defensive Crusader, the spellcasting Necromancer, and the stealthy Assassin.

Improvements from Hexen and Quake included destructible environments, mounted weapons, and unique level up abilities. Like its predecessor, Hexen II also used a hub system. These hubs were a number of interconnected levels; changes made in one level had effects in another. The Tome of Power artifact made a return from Heretic.