In Nightmare Dungeon, you play the role of Richard, an ex-factory worker turned paranormal instigator. One day, when investigating an unusual paranormal occurrence at an abandoned school, Richard gets lead into a Dungeon by a series of clues and linked events, a Dungeon which quickly seals behind him. The Dungeon is pitch black, While Richard panics to find a way out, a light flickers on, Richard see's written on the wall in what looks like blood, the words "Survive".
This is where the maze begins, from this point on, the monster will begin to stalk you.