Get the star cup in 50cc and get first place.
You have to get star or more in mushroom and flower cup.
To get King Boo, beat special cup in 1st place. But, there is no boo.
You can't unlock him. You can only play as "King Boo" on "Mario Kart Wii".
No, Boo isn't in Mario Kart Wii.However, King Boo is unlockable in the game by winning a gold trophy in the 50cc Star Cup.
King Boo
i guess only on Mario kart ds u can get another boo if u use boo because on Mario kart super circut( which i have and Mario kart ds too) i have never got another boo on that game BUT on Mario kart ds,i tried my first boo and got another boo!
50cc star cup
Win the 50cc Star Cup.
Toad, Toadette, King Boo, and Petey Piranha
king boo toad and toadettee and peaty pirahna
King Boo's fourth kart is the Aero Glider also known as the Jetsetter. To unlock it, you need to attain at least 1 Star Rank for all 150cc Retro Grand Prix Cups
King Boo, Bowser, Dry Bowser, Rosalina, and Funky Kong all use large karts on Mario Kart Wii.
if you win the star cup you unlock king boo but that's it