Several Mario Kart games let you choose King Boo as your champion of choice. He first made his Mario Kart debut as Petey Piranha's partner in Double Dash but has since chosen to drive alone.

Eight new racers have joined the Lego Mario Kart collection, including Wario, Bowser, Toadette, and King Boo.

King Boo's malevolent nature is fueled by a deep hatred for both Mario Brothers, leading him to trap Mario and Luigi in dangerous situations.