Illegus Episode IV is a first person maze game inspired by 3D Monster Maze. Your task is to make your way out of the 10 labyrinths of the planet Al-Mazar. The mazes are patrolled by robot guards. Contact with the guards is fatal, but they can be shot and killed. Warning of a nearby guard is sounded by an increase in the monotonic humming produced by a detector which you carry. Also within the maze are a variety of objects: gold, food, water and an infra-red viewer. The viewer is useful at night, when the maze would be otherwise invisible in the darkness. Later mazes also contain pits which can be jumped.