Death Note

A Shounen manga about a genius named Raito Yagami (most commonly known as Light Yagami) who is sick of the world. He finds a Note Book that says "if a name is written in the note, and the person who's name is written is imagined while it is being written, they will die." After learning the Death Note is real, Raito goes on a crusade to "become the God of a New World".