This story is a sequel to Terror in Equestria 11: Death and Destruction
After fusing the diamond heart into herself and freeing herself of evil, Supreme Commander Colgate is devastated by all the death she is responsible for. She wishes very much that she could take it all back and after a discussion with her generals, she decides that the only way to do it is to stop the very event that led the world down the path it took to begin with.