The Sun Won't Come Home

Princess Celestia gave her life fighting against Sombra. That's what the sources say. But Twilight is convinced she was transported to another dimension. Now, fifteen years later, she succeeds in following her.

Princess Celestia gave her life fighting against Sombra. That's the story everypony knows and tells and mourns every year. But Twilight is convinced she was transported to another dimension, and she won't let anything stop her from bringing the sun home.