Pingback

Pingback is an NES game.  It is literally a rom file that requires an emulator to play.  To further limit the accessibility of this game: the emulator needs to support Mapper 30.  
Mesen
Retroarch with FCEUMM Core
Are recommended.

Pingback is a short maze game.  Wander around and interact with things.  You have one key, and there are many doors, so be sure to use it wisely.  Nothing can hurt you, but you may be forced to restart from the beginning.

There is a good and best ending.  Finding the exit ends the game, getting all of the maze's residents to come with you will get the best ending.

While finishable, it is considered a WIP, and will continue to get better.