Bouncy Cloud

Bouncy Clouds are cloud platforms that appear in New Super Mario Bros. Wii, New Super Mario Bros. U, and New Super Luigi U. Anything that lands on them bounces very high, including enemies. Their appearance is reminiscent of Cloud Blocks, as both are white fluffy cloud featuring a smiling face in the middle.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, four of them appear in a secret area in World 2-6, and many of them appear in World 9-8.

New Super Mario Bros. U
In New Super Mario Bros. U, they appear in two levels, several of them can be found in the level Bouncy Cloud Boomerangs, and a single one is found in the final level of Superstar Road, Follow That Shell! When the player is not on a Bouncy Cloud, it opens its mouth in sync with the vocals of the music.

New Super Luigi U
In New Super Luigi U, they are also found in two levels, Above the Bouncy Clouds, and Flying Squirrel Ovation.

Super Mario Run
As of the version 3.0.4 update, a Bouncy Cloud appears as a Kingdom Builder object in Super Mario Run. It is a 3★ reward that can be won from Bonus Games.

Mario Party 9
In Mario Party 9, Bouncy Clouds are found in the minigame Buddy Bounce, where the players bounce on the clouds to collect the most balloons.