Heretic 2 - gamefront.com

A third-person action game based on the Quake II engine, Heretic II sets players on a quest through vast, city and outdoor environments as they search for a cure to a deadly evil plague before all is lost.
Using the Quake II engine, Heretic II plunges you into a deep, compelling game combining brutal face-to-face combat and mystery-laden adventure in the most advanced graphics engine yet. From a third person perspective, gamers travel through complex, richly detailed environments filled with stunning special effects, wicked magic spells, detailed characters, vivid artwork and challenging level designs created by the Raven team and reknowned fantasy artist Brom.