Bowser Jr.'s Boom Bunker

"My dad's gonna get angry if I let you get another Grand Star... Time to break out my Boomsday Machine!"

- Bowser Jr.

Bowser Jr.'s Boom Bunker is a boss galaxy in Super Mario Galaxy 2. Here, Mario will fight Bowser Jr.'s most powerful weapon, the Boomsday Machine. The main enemies here are Boomerang Bros. and Mines.

Planets
NOTE: Unless otherwise noted, all names are unofficial.

Starting Planet
The starting planet of the galaxy. There is a lot of mud on this planet, as well as a few Fizzlits and a Chance Cube. When Mario lands, various parts of Megahammer that Mario fought and defeated earlier in Bowser Jr.'s Fearsome Fleet are found destroyed, including Bowser Jr.'s Robot Cockpit. A single Bullet Bill still pops out of one of Megahammer's blasters however. There is a glass cage protecting a Cannon on top of the remains of one of the robot's arms. Mario must lure the Bullet Bill over here and have it destroy the cage to access the cannon and progress to the next planet. The entire Toad Brigade is also found here.

Boomerang Bros. Planet
A castle-like planet inhabited by two Boomerang Bros. There is a large target on one side. If Mario launches himself out of the cannon and hits it in the center, he will get a 1-Up. There are also several poles on this planet, and one of them has a Life Mushroom at the top. After defeating the two Boomerang Bros, a Launch Star leading to the next planet will appear.

Cannon Planet
This small planet has only a Checkpoint Flag and a cannon on top of it. Mario must shoot himself out of the cannon and onto another large target on the bottom of the next planet, but he must make sure not to hit one of the four Mines orbiting around the top of the planet. There is also a small electric fence extending partway around the middle of the planet.

Spinning Platforms Planet
After Mario hits the next target, he will find himself on a planet consisting mostly of many different colored platforms spinning around at various speeds with a Black Hole inside of it. The second set of platforms has Mines floating over them and a Comet Medal in between two more Mines. There are also a few Cloud Flowers here. Mario must use them to make his way to the top of the planet where he will Ground Pound more stone wheels to make the Launch Star appear. This will lead him to the final planet in the galaxy.

Dark Matter Planet
A large, rectangular-shaped planet with a few small platforms floating in Dark Matter. Following these, there is also a platform that tilts and moves while carrying Mario. He must move from side to side as the platform tilts back and forth and moves along so as to avoid touching the dark matter. At the end of the planet is a Checkpoint Flag and a Launch Star. This planet only appears in the Boomsday Machine Daredevil Run level, and replaces the Spinning Platforms Planet that appears in the regular level.

Boomsday Machine Planet
A cylindrical planet where Bowser Jr. waits in his Boomsday Machine to battle Mario. There are also multiple air vents located on the planet, which Mario must use in tandem with the Cloud Flowers found on the surface of the planet to propel himself upward where he must Ground Pound Bowser Jr.'s Boomsday Machine a total of three times to defeat it.

Bowser Jr.'s Boomsday Machine
In this mission, Mario must get a Bullet Bill to follow him and break open the cage which holds a cannon inside. Then, he must defeat the Boomerang Bros., use the Launch Star to get to the Midway Planet, and use the cannon to get to the Spinning Platforms Planet. Mario must then Ground Pound the stones on the other end of the planet and launch to the Boomsday Machine Planet. Here, Mario must defeat the Boomsday Machine by creating cloud platforms using the Cloud Flower and ground pounding the glass top. But with Mario en route to the machine's top, the Boomsday Machine will be shooting at Cloud Mario with electric balls that can disintegrate his clouds or shock Mario. After one hit, Bowser Jr. will activate vacuums that suck in the clouds in the arena, along with an electrical field in his cockpit, and still shoot at our hero. After two hits, the Boomsday Machine will expose its enormous, spiked, tank-like treads. To destroy the Boomsday Machine, Mario must climb to the top and hit it one more time, while avoiding the vacuums, electric field, and electric balls. Once he destroys it, Bowser Jr. is defeated, and Mario gets the Grand Star which opens the portal to World 6.


 * Enemies
 * Fizzlits
 * Bullet Bills
 * Boomerang Bros.
 * Mines
 * Planets Visited
 * Megahammer Planet
 * Boomerang Bros. Planet
 * Midway Planet
 * Spinning Platforms Planet
 * Boomsday Machine Planet


 * Names in other languages

Boomsday Machine Daredevil Run
The Daredevil Comet must be present in order to select this mission. Mario must get through this mission with one health. The level is the same as the first mission, except instead of the Spinning Platforms Planet, Mario must go though the Dark Matter Planet to get to the Boomsday Machine Planet.


 * Enemies
 * Fizzlits
 * Bullet Bills
 * Boomerang Bros.
 * Mines
 * Dry Bones
 * Planets Visited
 * Starting Planet
 * Boomerang Bros. Planet
 * Midway Planet
 * Dark Matter Planet
 * Boomsday Machine Planet


 * Names in other languages

Green Star 1
The player will have to break open the cage in order to get in the cannon on the Megahammer Planet. However, the player will notice the star above the target. The player will just have to shoot directly at the star with careful aiming and concentration, then the player may receive their reward.


 * Enemies
 * Fizzlits
 * Bullet Bills
 * Planets Visited
 * Starting Planet

Green Star 2
In order to get the next star, the player must jump in the cannon of the Midway Planet. However, when the player turns to the left, he or she will notice something sparkling in space. The player will have to use aiming, timing and concentration in order to get the prize.


 * Enemies
 * Fizzlits
 * Bullet Bills
 * Boomerang Bros.
 * Mines
 * Planets Visited
 * Starting Planet
 * Boomerang Bros. Planet
 * Midway Planet

Music
See here.

Trivia

 * The backdrop of this galaxy is extremely similar to the backdrop that is present in Bowser's Galaxy Reactor behind The Pathway, as both feature a large sun that is very close to these areas.
 * It is also the only Bowser Jr. level that does not feature a large blue-and-white planet orbiting in the background.