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Super Mario 3D All-Stars

Galaxy Overview

Ben Chard
Jarrod Garripoli
, &
Seren Morgan-Roberts


This page offers an overview of Bowser Jr.’s Robot Reactor Galaxy. Bowser Jr.’s Robot Reactor Galaxy is located in the Terrace dome and is final galaxy you unlock in this dome as well as containing the Grand Star.

Megaleg’s Moon

The goal of this level is to retrieve the Grand Star by simply defeating Megaleg. You will obtain the the Grand Star when you have freed it from it’s posession by destroying the casing housing the star.


This section offers a list of all enemies on this level.

  • Goombeetles – Goombeetles are Goombas who have helmets and therefore cannot be defeated by jumping on their heads. They will still head towards you like any regular Goomba but you will have to spin attack them with Y making them vulnerable to your hops, which will also give you a coin, or you can knock them into the planets core as they continue to spin around.

With the extra head protection, the Goombeetle likes to live life on the edge!

  • 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 any object.

Boss Enemy - Megaleg

Megaleg is a giant mech that will continually fire Bullet Bills in the area in an attempt to stop you. It carries the Grand Star on top of its head that is protected by a cage. You’ll need to lure the Bullet Bills to destroy the cage and the container to obtain the Grand Star and defeat Megaleg.

Don’t let this boss get the leg-up on you. Size isn’t everything!

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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

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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.

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