Clown Car

Clown Cars are a type of vehicle used commonly in Mario's World, particularly within the Koopa Troop. They're mechanical in nature, usually using a propeller to fly, and are often recognisable by their expressive clown-like faces, though not every model of Clown Car has this feature. They come in multiple sizes, shapes and colours and have many peripheral devices.

Mario & Luigi: Partners in Time
The earliest Clown Car seen chronologically is Bowser's in Mario & Luigi: Partners in Time. He was seen using it to escape the Vim Factory with Kamek after he took two Cobalt Star shards from the Mario Bros.. Since it had the same appearance then as it does when Bowser is an adult, it's entirely possible that the Koopa Clown Car is the original Clown Car of its type, or even as a whole, and that its clown-like features were designed specifically for the young prince.

Super Mario World
In Super Mario World Bowser used his Koopa Clown Car in the final battle against Mario in the Valley of Bowser. Here it's shown that Clown Cars can hold multiple Mechakoopas and Big Steelies, as well as Bowser and Princess Peach, all at once. The Clown Car's face is also shown to seemingly mimic Bowser's emotions, such as how it cries when Bowser is hit.

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