King Boo... What is there to say about the King of the Boos? Well, in recent appearances, he resembles a white Boo with a golden, five-pointed crown, though he is noticeably larger. As well, the crown has a blue jewel on the front and four red jewels around the sides in every game except Mario Super Sluggers. This King Boo first appeared in this form in Mario Kart: Double Dash!!, and it remains his current appearance to this day.