The Ruins of Abaddon

Harry didn't grow up like everyone thought he did. He grew up smart, sadistic and calculating which was only encouraged by his 'mentor' so to speak, a mysterious vampire named Thana. He grew up coached in all the arts and spent years hiding undercover as in the innocent Boy-Who-Lived. When he was fourteen, he meet Lord Voldemort and he changed the world. Dark BAMF Harry