Slenderman Easter Egg
The Slenderman Easter Egg is a little quirk found in the inaccessible town of Lavender Town in the southeast corner. The easter egg will result in Slenderman, a character from a creepypasta story, appearing for a few seconds.
To trigger the easter egg, simply interact with the poster in the corner of town. After the dialogue "Don't look. Or it takes you!", the player turns 180° only to see Slenderman. He remains on the screen for a brief two seconds, fleeing from the player by going into the wall to the left. This can be done how ever many times the player likes.