Bowser Jr.'s Boom Bunker

Bowser Jr.'s Boom Bunker.

Bowser Jr.'s Boom Bunker is the fifth boss galaxy in Super Mario Galaxy 2. It the last galaxy of World 5. To unlock this galaxy, one must get 55 Power Stars as well as one from the Space Storm Galaxy. This galaxy introduces the use of Cannons, which replace Launch Stars in most areas. Cannons only appear in this galaxy. Common enemies here include Boomerang Bros. and MinesMario/Luigi defeat Bowser Jr. once more, however, Bowser Jr. uses his most powerful machine, the Boomsday Machine


Starting Planet


Mario lands on the Starting Planet.

This is, hence the name, the starting planet of the galaxy. The are lots of mud here. The remains from Megahammer and Bowser Jr.'s Robot Cockpit from the battle in Bowser Jr.'s Fearsome Fleet are here. Despite the remains of Megahammer being destroyed, a single Bullet Bill will constantly be fired from one of his blasters. There is a glass sphere protecting the entrance to a Cannon. Mario/Luigi can let Megahammer's blaster fire a Bullet Bill and can backflip to get the Bullet Bill to spot him. With the Bullet Bill following him, Mario/Luigi must run across the planet avoiding Fizzlits and other obstacles that will slow him down and/or damage him, and then run behind the glass sphere, tricking the Bullet Bill into colliding with it. This destroys the cage and allows Mario/Luigi to drop into the hole with the Cannon. From inside the Cannon, Mario/Luigi must then fire themselves onto a target on the Boomerang Bros. Planet. If they hit the bulls-eye of the target, they are awarded with a 1-Up. Also, all members of the Toad Brigade can be found behind Megahammer's blasters; most of them will act scared when talked to because of the Bullet Bills being fired from Megahammer's blasters. 

Boomerang Bros. Planet

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Mario aims toward the target on the Boomerang Bros. Planet via the Cannon on the Starting Planet. If one looks carefully, they can spot a Boomerang Bro. waiting on them.

This is a castle-like planet inhabited by two Boomerang Bros. hence the name. There is a large target on one side that must be fired to via the Cannon on the Starting Planet in order to land on this planet. As mentioned above, a 1-Up is awarded to player for hitting the center of the target. There are several poles on this planet, which can be climbed. One of the poles 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

Bowser Jr.'s Boom Bunker Cannon Planet

Mario jumps into the Cannon's entrance, which resembles a green and yellow square hole. This is on the Cannon Planet. Some Mines and Electric Fences can be seen on this planet.

This is a small blue and yellow planet that has nothing but a Checkpoint Flag, the entrance to a Cannon on top (hence the name), and some Electric Fences which must be avoided. Using the Cannon on this planet, Mario/Luigi must fire themselves to another large target located at the bottom of the next planet. However, four Mines are orbiting this planet, which must be avoided when firing. To do so, Mario/Luigi should aim at the target on the next planet, wait for one Mine to pass their aim, and then quickly fire themselves to the target before the next Mine passes by. 

Spinning Platforms Planet

Bowser's Jr Platforming

Mario crosses the first set of spinning platforms on the Spinning Platforms Planet. The target that he had to fire to via the Cannon on the Cannon Planet can be seen at the bottom right of this picture.

After Mario/Luigi hits the next target, he will find himself on a planet made of many sets of different colored moving platforms orbiting the planet, hence the name "Spinning Platforms Planet". Underneath the platform is a large Black Hole which will suck the plumber in if they fail to land on a platform while making their way to the other side of this planet. The second set of platforms has Mines floating over them and the galaxy's Comet Medal can be found in between two more mines. There are also a few Cloud Flowers here, which must be used to make it to the other side of this planet. On the other side of the planet there is a safe platform with some stone wheels. These wheels must be Ground Pounded to make a Launch Star appear. This Launch Star will fire him to the Boomsday Machine Planet. 

Dark Matter Planet

Dark Matter Planet

Mario uses a moving, tilting platform to cross a river of Dark Matter during the Daredevil mission of this galaxy.

This is a large rectangular planet with a few small platforms floating in a river of Dark Matter. Following these, there is a platform that tilts and moves while carrying the player. Mario/Luigi must therefore move side to side to avoid touching the Dark Matter, which will instantly defeat them if they touch it. At the end of this planet there is a Checkpoint Flag and a Launch Star that will take Mario/Luigi to the Boomsday Machine Planet. It is to note that this platform only appears in the Daredevil mission of this galaxy and replaces the Spinning Platforms Planet in the first mission. 

Boomsday Machine Planet

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Mario battles Bowser Jr.'s Boomsday Machine on the Boomsday Machine Planet.

This is a large cylindrical which is the planet where Bowser Jr. waits in his Boomsday Machine for Mario/Luigi. Here, he will taunt the heroes before the battle begins. Multiple air vents (not to be confused with Lava Vents) are on this planet as shown in the picture to the right ---->. The player must use these vents along with the Cloud Flower's powers to propel himself upwards. Mario/Luigi must then use the Cloud Flower to reach the top of the Boomsday Machine and Ground Pound the glass windshield over Bowser Jr. three times to destroy the machine. 


Bowser Jr.'s Boomsday Machine


Mario battles Bowser Jr.'s Boomsday Machine during the mission "Bowser Jr.'s Boomsday Machine".

Mario/Luigi will land on the Starting Planet. Here, they will find one of Megahammer's blasters firing Bullet Bills. Mario/Luigi must get a Bullet Bill to notice him so that it homes in on them. They can do so by backflipping in the air close to the blaster when one is fired from it. Once a Bullet Bill is following them, Mario/Luigi must run across obstacles to reach a glass sphere at the end of the planet. Here, they must go behind the sphere to trick the Bullet Bill into colliding into it, destroying it. Now that the sphere has been destroyed, Mario/Luigi must fall into a green and yellow hole that the sphere was covering. A Cannon will catch them and the player will be taken to the aim screen. Here, the player can see a target on the Boomerang Bros. Planet. The two must aim at this target to safely land on that planet. If they hit the center of the target, a 1-Up is given to the player. However, if the player misses the target, he will find himself flying into Space (even though you are really flying close to the giant sun in the backdrop of the galaxy) and will lose a life. Anyway, when the heroes safely reach the target, they will find two Boomerang Bros. ready to put up a fight. There is a Life Mushroom above one of the poles on this galaxy. After the two Boomerang Bros. are defeated, a Launch Star appears, which will blast the player to the Cannon Planet. Here, the player must avoid some Electric Fences here and drop into another green and yellow hole. A Cannon will catch them. The player must now aim and fire at a target at the bottom of the Spinning Platforms Planet. BUT!!! There are four Mines that orbit this planet and will pass the aiming screen every few seconds. To avoid firing into one, the player should aim at the target on the Spinning Platforms Planet, wait for a Mine to pass by, and then fire themselves onto the target. On this target, the player will find several rows of platforms spinning around the planet. Beneath them is a Black Hole. So, Mario/Luigi must cross these platforms to reach a safe platform on the other side of this planet. The Comet Medal is found here and must be collected wisely in order to safely reach the safe platform on the other side of this planet, otherwise the player will find himself sucked into the Black Hole and back onto the Cannon Planet. Anyway, at the safe platform at the other side of this planet, the player must Ground Pound several stone wheels to destroy them, causing a Launch Star to appear. The Launch Star will blast the player onto the Boomsday Machine Planet. Bowser Jr. is waiting here in his Boomsday Machine. He will taunt the player before the battle begins. Once the battle begins, the first thing to do is collect a Cloud Flower here. After doing so, Mario/Luigi should stand on one of the air vents to be propelled upwards. Using the Cloud Flower, they must create Cloud Flowers to reach the glass windshield at the top of the machine, while avoiding the electric balls that Bowser Jr.'s Boomsday Machine fires. The player should Ground Pound the windshield three times to destroy the machine. However, Bowser Jr. gets angry after the second Ground Pound on his windshield protecting him. Therefore, he will create an electric attack over his windshield every few seconds. If the player Ground Pounds the windshield during this attack, they will be shocked and sent back to the ground. They must then repeat the process and Ground Pound the windshield, this time when the electric attack stops for a few seconds before starting back. After the third and final Ground Pound on the windshield, the Boomsday Machine is destroyed and Bowser Jr. is defeated completely for the rest of the game. He releases a Grand Star to the player, which unlocks World 6 when collected. 


Planets Visited

  • Starting Planet
  • Boomerang Bros. Planet
  • Cannon Planet
  • Spinning Platforms Planet
  • Boomsday Machine Planet

Boomsday Machine Daredevil Run

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Mario battles the Boomsday Machine with only one wedge of health.

To unlock this mission, the player must collect the Comet Medal during the first mission (Bowser Jr.'s Boomsday Machine), which will cause a Daredevil Comet to orbit the galaxy. This mission is a repeat of Bowser Jr.'s Boomsday Machine, however there are two differences. The first difference is the fact that the player has only one wedge of health on their Health Meter throughout the entire mission, meaning that one hit from any enemy or obstacle will instantly defeat them. The second difference is the player must cross the Dark Matter Planet instead of the Spinning Platforms Planet. 


Planets Visited

  • Starting Planet
  • Boomerang Bros. Planet
  • Cannon Planet
  • Dark Matter Planet
  • Boomsday Machine Planet

Green Star 1

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Mario fires toward the first Green Power Star in the galaxy.

The player must redo "Bowser Jr.'s Boomsday Machine". When they land on the Starting Planet, they must lure a Bullet Bill into the glass sphere to gain access to the Cannon. Here, they will be able to see the star above the target on the Boomerang Bros. Planet. The player must aim and shoot to the Star, however, very good aiming is recommended or the player will find themselves shot towards the giant sun in the backdrop, causing them to lose a life. 


Planets Visited

  • Starting Planet

Green Star 2

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Mario fires himself to the second Green Power Star in the galaxy.

The player must redo "Bowser Jr.'s Boomsday Machine". Here, they must jump into the Cannon on the Cannon Planet. If they aim left, they will see something sparkling in Space. They must then aim and fire to reach the Star. However, they must avoid the Mines orbiting the planet, as well as aim very well, as they can end up flying into Space, causing them to lose a life. 


Planets Visited

  • Starting Planet
  • Boomerang Bros. Planet
  • Cannon Planet


  • This galaxy is the only Bowser Jr. boss galaxy that has a giant sun in the backdrop instead of a large blue and white planet that resembles the Earth (Bowser Jr.'s Fiery Flotilla and Bowser Jr.'s Fearsome Fleet have this planet in the backdrop as seen on their pages). 
  • This galaxy is very similar to Bowser's Galaxy Reactor in Super Mario Galaxy, since they both have giant suns in the backdrop/background. However, Bowser's Galaxy Reactor has a giant sun in the background on The Pathway, while this galaxy has a giant sun in the backdrop/background that can be seen throughout the entire level. 


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