Square cloud

The Lakitu Block is a block found in World 4-5 of New Super Mario Bros. Wii; it is white and has a smile on its front. When activated, a Lakitu will appear and start to toss coins on the floor, which Mario and his company can then collect. However, there are also other Lakitus that throw Spinies present in the level, which the player can easily mistake for the coin-throwing Lakitu. Just like any other Lakitu, however, the player can get injured if they touch the Lakitu throwing the coins.

Trivia

 * The way the Lakitu throws coins is reminiscent to Super Mario World when a cloud appears and drops coins with smiley faces on them after Yoshi has eaten two pink Berries.