King Boo

King Boo is the leader of all the Boos. He is a ghost and loves haunting children and giving them nightmares. King Boo has also kidnapped Mario a few time but is always saved by Luigi in a very quick span of time. King Boo has also done other evil things. He just like other Boos was born a ghost and will always be one. He also races in the Mario Kart tournaments as well.