Harry becomes evil, because of the abuse of his relatives, the death of Sirius, the betrayal of his friends and a man who thinks of him as a wise teacher.

Abused by his relatives and everyone, Harry fall to dark side and grew stronger and wants revenge over everyone, Full of Darkness as Harry embarces on his own quest to "destroy the wizarding world".

After Harry killing Bellatrix, Harry begins to fall to the dark side, and learns that his friends are hiding secrets from him.