Bumper Sparks

Bumper Sparks is a Bowser Jr. minigame in Mario Party 9. Its name is most likely a pun on "s," an amusement park attraction.

Introduction
Bowser Jr. runs into his Junior Clown Car and turns around to face the camera. The camera then zooms out to show the entire playing field.

Gameplay
The pair must try to knock Bowser Jr. into the electric rail three times before time runs out. Players bounce off each other and Bowser Jr. If a player hits the fence, they are stunned temporarily, but if Bowser Jr. hits the fence, he loses a heart and returns to the center, temporarily invincible. Bowser Jr. generally does not try to attack the players, but he sometimes leads them into the electric fence. If the pair fails to knock Bowser Jr. into the fence three times in 30 seconds, he is victorious.

Ending
If the players are victorious, Bowser Jr. and his Junior Clown Car go flying off the screen. If Bowser Jr. is victorious, the electrified ring gets powered off as the players groan, and Bowser Jr. laughs and flies away.

In-game text

 * Rules – "Ram into Bowser Jr. to knock him into the electrified ring around the platform. Knock him into the ring three times to win!"
 * Controls – "Hold the Wii Remote sideways. Tilt the Wii Remote in the direction you want to move your vehicle."

Trivia

 * This is very similar to the boss battle against Topmaniac in Super Mario Galaxy, and is almost identical to the battle against Bowser Jr. on the second airship of New Super Mario Bros. Wii. Also, the sound played during this battle is a slowed-down version of the original.

Bowser Jr.-Scooter