The Thunder Cloud is a item that zaps you with thunder. It speeds you up before getting zapped. You can pass it on to others by colliding with their car or bike. If not, the cloud zaps you, shrinking you and slowing you down (the same effect as a Thunderbolt.) Warning: If you get this item while playing online, it will be hard to pass this item to another racer because they will drive so fast that you will get shrunk. Because of how bad this item is, the Thunder Cloud only appears in Mario Kart Wii.