When we slid into Pinkie's Party cave, some of us learned Pinkie's party plans. But when I got to read my dossier, in private, I learned something that might change the trajectory of my entire life.
My special talent had turned my life into a waking nightmare of moral and life-or-death decisions. I hoped visiting cousin Apple Bloom, who'd survived her own cutie mark nightmare, might help me decide whether to keep my cutie mark... or remove it.
Starlight Glimmer destroys Equestria when she learns how she actually lost her soulmate, Sunburst. Fixing her mistake, she learns time travel can lead to a revelation of the heart and the renovation of harmony. (An alt-ending to The Cutie Re-mark.)