Strife

Strife: Quest for the Sigil, released in 1996 (usually shortened to "Strife"), is a Doom engine game created by Rogue Entertainment and published by Velocity. It offered an RPG-like action game, with heavy story elements and voice-acting. Among the features were hub-levels similar to Hexen, the ability to increase the player's accuracy with most of the weapons, an item that could destroy forcefields, and the ability to raise your maximum health from 100 to as much as 200 permanently, similar to Doom. Strife is also the very last commercial game to use the Doom engine. Its source code was lost.

As of 2014, the game can now be played on any system that can run ZDoom (e.g. Mac OS and Windows).

Story
A comet has hit the Earth, unleashing a virus and killing a large amount of the populace. A lot of the survivors started to hear the voice of a god in their heads (The Entity) and worshipped it. The Order took over the world and all women and children found were killed, forcing the survivors to go underground, while the men became peasants. The Order's rule is brutal and oppressive to the extent an underground resistance is formed. Calling themselves the Front (although in the shareware version it is referred to as 'The Movement'), they struggle to free themselves from the Order. However, the Order's technological advantage has damped the Front's efforts.

The following is as it is explained in the manual of the game: "You are a wandering mercenary, led to the small town of Tarnhill by rumors of conflict between The Order, a well-equipped religious dictatorship, and The Front, the rag tag resistance movement. While searching for The Front you decided to take a brief rest somewhere that you thought was safe. The Order acolytes have been rounding up all suspicious characters in the area. Yes, you happen to be one of them. What they didn't expect, though, is the knife you keep concealed for situations just like this one..."