After the slaughter of D'sparil, Corvus ends up on a perilous journey with little hope to return home. After defeating them, the player must seal the portal and so prevent further infestation, but after he enters the portal guarded by the Maulotaurs, he finds himself inside D'Sparil's dome. At its end is the gateway to Hell's Maw, guarded by the Iron Liches. The player must first fight through the undead hordes infesting the site where the elders performed their ritual. He travels through the 'City of the Damned', the ruined capital of the Sidhe (its real name is revealed to be Silverspring in Heretic II), then past Hell's Maw and finally the Dome of D'Sparil. While the Sidhe retreat, one elf (revealed in the sequel to be named Corvus), sets off on a quest of vengeance against the weakest of the three Serpent Riders, D'Sparil. The Sidhe are forced to take a drastic measure to sever the natural power of the kings destroying them and their armies, but at the cost of weakening the elves' power, giving the Serpent riders an advantage to slay the elders. The Serpent Riders thus declared the Sidhe as heretics and waged war against them. The Sidhe elves resist the Serpent Riders' magic. Three brothers, known as the Serpent Riders, have used their powerful magic to possess seven kings of Parthoris into mindless puppets and corrupt their armies. Heretic II was released in 1998, which served as a direct sequel continuing the story. An indirect sequel, Hexen, was released a year later. All music in the game was composed by Kevin Schilder. The game used randomized ambient sounds and noises, such as evil laughter, chains rattling, distantly ringing bells and water dripping in addition to the background music to further enhance the atmosphere. Previously, the character would simply crumple into a heap. It also introduced multiple gib objects spawned when a character suffered a death by extreme force or heat. Using a modified Doom engine, Heretic was one of the first first-person games to feature inventory manipulation and the ability to look up and down.

It was made available on Steam on August 3, 2007. Heretic is a dark fantasy first-person shooter video game created by Raven Software, published by id Software, and distributed by GT Interactive in 1994. Unfortunately, this game is currently available only in this version. If you prefer to use a java applet emulator, follow this link. This game is emulated by javascript emulator em-dosbox. For fullscreen press 'Right Alt' + 'Enter'. Game is controlled by the same keys that are used to playing under MS DOS.

Heretic game press release