This mini-game is unlocked only when the Star Battle Arena is completed, and then it is playable in Mini-game Mode.
Bowser and the character are each in space, and the character has the Star Rod in his/her hand. Bowser is riding on the Koopa Clown Car(from Super Mario World),and the player is on a Warp Star-like Star.
On Disc Rules
RULES: Bring down Bowser!!! Wave the Star Rod over your head to build energy. Shoot once you're charged up! Hint: Watch Bowser carefully. When he launches an a attack,head on the defensive, even if you're charging up.
This is a one-player game. Bowser has 10 life points, and the player has 5. While Bowser blasts fireballs, the player must hold the Wii Remote up, and swing it around to charge up the Star Rod, while dodging Bowser's flames. After it is charged, the player will swing down his/her arm to throw the energy ball. After hitting Bowser 3 times, the game goes to phase 2.
Now Bowser has two Bullet Bill launchers. They fire around 6 Bullet Bills each time. This makes it harder for the player, as he or she has to dodge the missiles. After hitting him 3 times again, the battle enters phase 3.
This is the last phase. Now, in addition to the weapons he had before, the vehicle he's riding will have a laser blaster, which will rotate, sending beams out. The only way to dodge these is to get in between two of them. Also, the Bullet Bills will become red and move faster. When Bowser has two lives left, he will fire a large fireball, in addition to the other attacks. After blasting Bowser one more time, the player beats the game.
After being hit by the final blast from the Star Rod, Bowser, still inside the Koopa Clown Car, is sucked downward into a Black Hole-like vortex. thumb|300px|right