Released in 1994 for DOS only, Heretic is the first game in the Heretic / Hexen franchise. It uses the engine from id Software's DOOM and transplants that game's first person shooter gameplay into a fantasy setting.
Hexen: Beyond Heretic is a first-person shooter developed by Raven Software and released in 1995 as a sequel to Heretic, published one year before. It is the second chapter of the Serpent Riders series.
Black Crypt is a fantasy single-player role-playing game by Raven Software, published by Electronic Arts. It was released in 1992. It was originally conceived of as a pen and paper roleplaying game by Brian Raffel and Steve Raffel.