Once the monster starts to chase a certain guy, thinking that it is a fruit of its imagination it addresses for medical aid. To it make the diagnosis mania of prosecution.
Passes some time, but treatment to it does not help, hallucinations and visions do not pass, the monster starts to steal up so close that he starts to feel its breath, soon having realised that this monster at all a glitch, and a reality he starts to search for a way out....
During 8 levels the hero should jump, run to make a start from walls escaping from the monster. The modern city, steppe, the ancient lock and its roofs enter into zones and locations.
Gradually complexity increases, and to pass corridors filled by traps all it becomes more difficult.