A Game of Chess

The war is all but over, and the wrong side won. Worse, the Wizarding World's hero and Ron Weasley's best friend died in the fight. When Draco Malfoy offers Ron a way to go back and fix things, he jumps at the chance. But can he anticipate how his changed moves will affect the board?
[Trope stew: this fic began as an exercise, an attempt to use problematic or challenging tropes. A meta-discussion of each trope to follow each chapter.]