Leon's the son of a rich scientist who also is a super villain called Green Goblin. He's been wreaking havoc of Raccoon City, ultimately getting killed by you who got bit by a radioactive spider. Leon was devastated at his father's death that he swore he'd kill who did it to him. After a few months, he finds out that you're the one who got his father killed. Out of rage, he plans out a way to kill you.