Harry Potter: the Return of Salazar Slytherin

"Ah, my research was successful!" Salazar Slytherin was resurrected after being buried for a thousand years. After waking up, he returned to Hogwarts anonymously with the little wizard's body, and then he was shocked to find: In ancient times, some families who indulged in Muggle lust or were simply Muggle-born claimed to be pure-blood families. The madman who appeared as his descendant became the dark lord that people talked about, promoting extreme ideas under his own banner. "Where are the records of all the powerful spells and charms?" "Although all kinds of magic spells have become fancy, wizards' bodies are extremely weak, even the descendants of Gryffindor are no exception." (Note: Some parts of the story may be different from the original work, and there will also be some butterfly effects)