The Dark Arts Professor at Hogwarts

[Second time travel + no heroine + fun person + invincible] Several centuries ago, Levi came to this world from a continent full of magic and war. With the various races that followed him into this world and his outrageous magic Successfully helped Merlin, who was still a magic apprentice, successfully unify the entire province. But he was betrayed by Merlin, and combined with the extraordinary powers in this world, stabbed him in the back and sealed him in a sarcophagus. On the day he is dug out by Death Eaters, the wizarding world will finally welcome the most terrifying Leziman. In this world where spells with direct death effects are banned, what kind of waves will the magic in Levi's hand that is aimed at legion combat cause? Why did Dumbledore's bird burst into flames? Why did Snape wash his hair? Why is the giant dragon hovering in the sky howling? While wandering around the world, Levi also discovered that this world did not seem to be entirely dominated by wizards. [Some American drama settings will be inserted later]