From the Super Mario Wiki
The Rainy Balloons are an unlockable glider in Mario Kart Tour. They are a variation of the Cloud Glider with a darker color scheme resembling Lakithunder's cloud and are classified as a tour-exclusive High-End glider. When this glider is equipped, striking other drivers with a Lightning grants more points than usual.
The glider was exclusively obtainable during the Halloween Tour and was part of the second week's spotlight alongside King Boo (Luigi's Mansion) and the Ghost Ride. It is now exclusive to the Hammer Bro Tour and is part of the first week's spotlight, alongside Hammer Bro and Boomerang Bro.
Names in other languages