|The Thunder Cloud in Mario Kart Wii.|
|Description||A transferable lightning-like item that shrinks the player that has it.|
|First appearance||Mario Kart Arcade GP (2005)|
|Latest appearance||Mario Kart Arcade GP DX (2013)|
When this double-edged sword is picked up, a cloud will appear above the player, speeding their vehicle up by a notable amount and negating off-road penalties completely. After a short amount of time, however, the cloud will zap the player with lightning, just like the Lightning Item, leaving them wide open to incoming attacks or other racers. The cloud may disappear when the holding player travels through a cannon or uses an invincibility item. The item may also be passed on from person to person; the duration of the cloud does not reset when passed, allowing daredevil racers to hold onto the cloud for a very long time to catch up and then bump into another player just as it is about to strike.
- Due to the one-of-a-kind nature of the Thunder Cloud, glitches have arisen based off of it. Hackers may forcefully spawn multiple Thunder Clouds and pass them onto different players; the previous Cloud spawned in this manner will disappear, but players afflicted will remain boosted for the entirety of the race.
- The clouds zip sound gets faster as it gets closer to striking.