Dying Light - Super Mario Easter Egg
In the southern portion of Old Town you'll find a green pipe which is located in the middle of the chimney (pictured above). Approach it and press F while ontop of it to enter "World 1-1" which will put you in an area just off the map and underground which resembles a basic Super Mario level. To complete this level run to the end of the course and avoid the exploder zombie.
There is also a Blueprint Hidden in this level for you to find as well.
Watch my video below if you'd like to see me complete this Easter Egg.