Upon arriving at Platform 9 3/4 after their sixth year Voldemort inflicts a curse on Harry that transfers all magic to him. Hermione and Harry get together. He trains with the goblins and faces Voldemort down with their help by extracting all magic from him and decapitating. Then he blows everything up. On the face of it he is killed but comes back to Hermione as Marcus Steward.
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