Junior Clown Car

The Junior Clown Car (originally dubbed the flying carriage ) is Bowser Jr.'s favored mode of transportation. It is a miniature version of Bowser's Koopa Clown Car, chock full of gadgets and gizmos. Despite being called a car, it is a helicopter-like vehicle with an innocent clown face on the front, which has the ability to change its expression.

New Super Mario Bros. Wii
In New Super Mario Bros. Wii, the Junior Clown Car is introduced, although not yet named. Bowser Jr. uses his vehicle twice in battle, and for the third time he ditches it for the original clown car. Mario, Luigi, Yellow Toad, and Blue Toad can also ride smaller copters exclusively in. These smaller copters highly resemble a usual Clown Car, except it lacks a face and feature an M or L, or a yellow or blue mushroom logo on it depending on the player. Shaking the Wii Remote produces a move similar to that of a Spin Jump, and crashing into Bowser Jr. with this maneuver is required to shove him into the surrounding electricity.

New Super Mario Bros. U
The Junior Clown Car returns in New Super Mario Bros. U. Like with the Koopalings stylizing their Airships, Bowser Jr. has customize his Junior Clown Car with various enhancements, including one with boxing gloves. Similar to the Paper Mario version of the Koopa Clown Car and Junior Clown Car, Bowser Jr.'s boxer car has its angry face on for the entire time.

Bowser Jr.'s first enhancement, an aquatic submersible-type, fights against Mario. Like past encounters, it has a happy face on initially, although it briefly resorts to its angry face when firing Torpedo Teds. After he is defeated the first time, he uses the boxer variation in his second battle, which also contains a payload of Bob-ombs.

Bowser Jr. later uses his standard Junior Clown Car to fight Mario alongside Bowser. Unfortunately for him, Mario is able to pounce him and carjack him, as well as use the vessel to ram into his father's head. Bowser Jr. later uses it to escape when Bowser inadvertently destroys what was left of the Airship, with Bowser and the Koopalings holding on (the latter via the former's tail).

Paper Mario: Sticker Star
The Junior Clown Car appears in Paper Mario: Sticker Star. It's mostly used as his mode of transportation, but Bowser Jr. uses it during his battle in Bowser Jr.'s Flotilla, where it shoots either fireballs or Spiked Balls.

Super Smash Bros. series
Bowser Jr. and the Koopalings make their Smash series debut as "unlockable" ("starter" in the Wii U version) newcomers in Super Smash Bros. for Nintendo 3DS and Super Smash Bros. for Wii U. Each Koopaling drives a specific-colored Junior Clown Car that have yellow eyes instead of black like Bowser Jr.'s version. They all fight identically, however. According Palutena in her guidance, the Koopalings' version of the Junior Clown Car is the mass-produced type, with Pit concluding that Bowser Jr. must have preferential treatment.

Mario Party 9
In Mario Party 9, Bowser Jr. is seen in Pair of Aces in his Junior Clown Car. When the players reach the end of a stage, Bowser appears in the Koopa Clown Car as well. Bowser and Bowser Jr. also ride their respective vehicles in the ending. Additionally, in the Bumper Sparks minigame, players use vehicles very similar to the Junior Clown Car's playable counterparts to bump into Bowser Jr. to try to bump him into the electric barrier, just like New Super Mario Bros. Wii.

Mario & Luigi: Dream Team
Bowser Jr. and the Junior Clown Car both appear as the final boss of the Battle Ring in Mario & Luigi: Dream Team. While it is not his vehicle's debut, it is officially named the Junior Clown Car for the first time. It guards him from attacks and at one part in the battle becomes its own enemy target separate from Bowser Jr.

When Mario or Luigi tries to use the Jump attack on the Junior Clown Car while Bowser Jr. is outside the Clown Car, they will not attack it, but instead will get in it, to throw stuff at Bowser Jr.

Trivia

 * Super Smash Bros for Nintendo 3DS / Wii U are the only two games where the Junior Clown Car is portrayed with an actual car mode.