Being the Master of Death was not just a ceremonial title. Harry soon learns of his new responsibilities, and where he can do the most good.
Harry Potter is tired of running blindly into life and death situations. This series is about Harry thinking before he leaps. It starts off at the summer following the events that transpired in Prisoner of Azkaban.
As the Death Eaters chased Harry and his friends through the Department of Mysteries. Harry stumbles upon a room that changes everything before it ever happens. Alternate canon verse.