Heretic and Hexen shipped a combined total of roughly 1 million units by August 1997.While remarking that Heretic is a thinly-veiled clone of, and that its being released in Europe after and with due out shortly makes it somewhat outdated, Maximum nonetheless regarded it as an extremely polished and worthwhile purchase. The version of a console port for the was also released.Reception ReceptionAggregate scoreAggregatorScore62%Review scoresPublicationScore78%MaximumHeretic received mixed reviews, garnering an aggregated score of 62% on and 78% on. This resulted in ports to, and other operating systems, and updates to the game engine to utilize 3D acceleration. If the player uses the 'god mode' cheat (' IDDQD') from Doom, the game will display a message saying 'Trying to cheat, eh? However, if the player uses the 'all weapons and keys' cheat (' IDKFA') from Doom, a message appears warning the player against cheating and takes away all of his weapons, leaving him with only a quarterstaff. However, the rendering method for looking up and down merely uses a proportional pixel-shearing effect rather than any new rendering algorithm, which distorts the view considerably when looking at high-elevation angles.As with Doom, Heretic contains various cheat codes that allow the player to be invulnerable, obtain every weapon, be able to instantly kill every monster in a particular level, and several other abilities. Heretic also features an improved version of the Doom engine, sporting the ability to look up and down within constraints, as well as fly. One of the most notable pickups that can be found is the 'Tome of Power' which acts as a secondary firing mode for certain weapons, resulting in a much more powerful projectile from each weapon, some of which change the look of the projectile entirely. These items range from health potions to the 'morph ovum', which transforms enemies into chickens.

Heretic game monsters