King Boo first appeared in Luigi's Mansion, as the final boss. King Boo kidnaps Mario, and it's up to Luigi to rescue Mario with the help of the Poltergust 3000, a vacuum he recieves that is use to suck up ghosts. King Boo also makes an appearance in Super Mario Sunshine and Super Mario 64 DS as a boss (though his name was Big Boo, it is either a mistake, or his full name), and is a playable character in Mario Kart: Double Dash!! and Mario Superstar Baseball. One of Mario's helpers from Paper Mario, Lady Bow, is his daughter.