After losing Hedwig while escaping from Voldemort, Harry found it hard to come to terms with her death. 

Filled with grief, rage and hatred, Harry swears to take revenge on every single death eater and especially on Voldemort himself.

Receiving power from unexpected sources, Harry sets out on his mission to bring the dark lord and his followers to their knees.

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This novel has been posted on Webnovel, Scribblehub, Fanfiction and RoyalRoad.

During the final rewrite, the plot changed so much that it was nothing like this one. So I posted it as a new story instead. Please go read that instead. It is called Harry Potter and the Dark Phoenix. If I have time, I might finish this book with the current plot, but I don't have any plans as of now.