These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Complete Monster: Bishop Breathstar, and Overseer Slademare, watch hundreds die solely to keep their control over Dredgemane and mining operations rolling. They oppose medical research to cure diseases because it would disrupt the misery they built their positions on.
Tearjerker: Basically any back story that comes up from the fact that the entirely of Equestria has just died in a disaster, which may have taken long enough for them to be aware of what was happening. To Fluttershy’s parental problems and the history of Dredgemane.