Celestia loved seeing her sister roaming her dreamscape and teaching lessons in her sleep, but now, when Celestia has a quite disturbing nightmare that Luna doesn't seem to know about, Celestia worries about how to protect her sister in her dreams, a land that never really was Celestia's. Celestia must now face a rising monster who raises monsters and seems to have created fear itself.

Also, if you are looking for some big adventure with a climax and stuff, this is a serial. So that story with an ending is somewhere else...

This is my entry to the Summer 2017 picture prompt contest on the group, Nightmare Moon Is The Best Pony