Updated Title Publisher
Updated Title Publisher
Updated Title
Published Title Score Editor's Choice
Published Title Score

Super Mario 3D All-Stars

Galaxy Overview

Ben Chard
Jarrod Garripoli
, &
Seren Morgan-Roberts


This page offers an overview of Bowser’s Galaxy Reactor. In this galaxy, you’ll find the final level of the main story. This galaxy will become available to you once you’ve collected 60 Stars and completed Darkness on the Horizon.

Fate of the Universe

This is the final boss level against Bowser. Your goal is to make your way through Bowser’s Galaxy Reactor to reach the final boss fight.


  • Dry Bones - Dry Bones are skeleton versions of Koopa Troopas. They cannot be defeated permanently but jumping on them will temporarily incapacitate them.

  • Fire Bars - Fire Bars are obstacles that you’ll need to navigate around. They’re not hostile or animate, but they will definitely get in your way! If you touch one, you’ll be burned causing you to jump around frantically.

  • Fireballs - The Fire Balls will pop out of the lava. If you’re hit by one, you’ll take fire damage.

  • Bullet Bills - These Bullet Bills will lock onto you and fly towards you if they spot you. The best way to defeat them in this level is to guide them into flying towards the stone statues so they explode.

  • Banzai Bills - The Banzai Bill is a giant Bullet Bill. You cannot defeat it so you’ll just need to get out of its way. Luckily, he doesn’t lock on to his victims like Bullet Bills.

The Banzai Bill is scary, but arguably easier to avoid compared to the Bullet Bill.

  • Thwomps - Thwomps will crush Mario and defeat him instantly if he is standing beneath them when they crash down. You cannot defeat them in this level, so you’ll just have to avoid being crushed by them.

  • Thorny flowers - Thorny Flowers are spiky plants that will damage you if you touch them. You cannot spin attack or groundpound them and the only real way to defeat them is with a Rainbow Star power-up or a green sprout. None of which are available in this level, unfortunately.

Boss Fight - Bowser

Since this is the final Bowser boss fight, it is much longer than the usual Boss fights. It has three stages and takes place on three separate planets.

Boulder Bowser

In the first phase, Bowser will encase himself in a boulder. To damage him, you’ll need to spin attack his head. He looks like the usual boulders found within the other galaxies, so damage him like you would a typical boulder. When you’ve broken his boulder exterior, you’ll need to catch up with his spinning shell and spin attack him. You need to do this twice in order to move on to the next section of this fight. On the second attack, you’ll need to spin attack him twice in order to get in some damage.

Smash Boulder Bowser by spin attacking his exposed face.

During this boss fight, you’ll also need to be careful of Bowser’s signature attack moves:

  • Fire Balls - He will spit out a few fireballs and they will bounce around for a bit before disappearing. They are easy to avoid but will inflict fire damage if they hit you.

  • Electric waves - When he jumps, Bowser will create circular electrical waves that go around the entire planet. To avoid them, you’ll need to jump over them. Sometimes he will create up to 3 consecutive rings that you’ll need to jump over one after the other to avoid.

  • Groundpound - When close to you, Bowser will attempt to groundpound you. You can easily get out of the way of these attacks. You will also need to utilise these groundpounds to take him down during this boss fight.

Spiky Bowser

During this phase, you will need to use the green sprouts to attack Bowser whilst he is spinning in his spiky shell. To do so, you’ll need to lure his spiky shell over to one of the many sprouts and then spin attack the sprout so it bounces straight into Bowser. This will cause him to spin about the planet, allowing you to catch up to him and spin attack him. You’ll need to do this twice to complete this section of the boss fight. On the second attack, you’ll need to spin attack his spinning shell twice to damage him.

You’ll need to use the green sprouts to knock Bowser’s spinning spiky shell.

After you’ve done this, you’ll drop onto a new planet, where you’ll begin the final phase of this level.

Bowser’s Final Phase

This fight is identical to the previous Bowser boss fights in other galaxies. You will need to get him to groundpound on the blue domes so he burns himself in the lava beneath. Once more, you’ll need to watch out for his fiery balls and his laser rings. When you’ve successfully managed to get him to burn himself in lava, catch him as he’s hopping around with a burning tail and spin attack him. Then, run the opposite direction to where his shell spins to catch him on the otherside of the planet. Spin attack him again to deal some real damage. You’ll need to perform this process twice to defeat him for good. When you’ve gotten him to burn himself the second time, you’ll need to spin attack him three times to damage him.

No Comments
Guide Information
  • Publisher
  • Platforms,
  • Genre
    Action Adventure, Platformer
  • Guide Release
    24 September 2020
  • Last Updated
    8 February 2021
    Version History
  • Guide Author
    Seren Morgan-Roberts, Jarrod Garripoli, Ben Chard

Share this free guide:

This guide for Super Mario 3D All-Stars offers a walkthrough for all three Mario classics.

Inside this guide you will find:

A 100% Walkthrough - For Super Mario 64, Super Mario Sunshine and Super Mario Galaxy.

A complete guide on Super Mario 64, including:

  • A layout of Peach’s Castle, with each course’s location pinpointed, as well as an overview of each course.
  • Walkthroughs for every star, including all courses’ 100-coin star.
  • How to get each of the power-up caps.
  • The location of every single Secret Star found in Peach’s Castle.

A complete guide on Super Mario Galaxy, including:

  • A Dome Overviews page outlining every galaxy found in each Dome.
  • Walkthroughs for every star, including hidden stars and comet stars, found in each galaxy.
  • A guide on how to unlock the Planet of the Trials galaxies.
  • Detailed coin-by-coin walkthroughs of Purple Coin levels.

A complete guide on Super Mario Sunshine, including:

  • Walkthroughs for every shine in every episode.
  • How to find every Blue Coin.
  • Strategies on how to secure 100 Coins on every Course.

Get a Gamer Guides Premium account: