Strife: Quest for the Sigil is a hybrid first person shooter and role playing game built on the Doom engine, created in 1996 by Rogue Entertainment and published by Velocity Incorporated. Uniquely amongst Doom engine games, it contains heavy plot and story elements throughout gameplay, supported by interactive characters with professional voice acting. Choices are given to the player through a dialogue system, some of which can impact the ending of the game. Other added features were hubs similar to those found in Hexen, an inventory, the ability to increase the player's accuracy with most of the weapons, an item that could destroy force fields, and the ability to raise the player's maximum health from 100 to as much as 200 permanently. Strife is the very last licensed game to use the Doom engine. Its source code was lost.