This page offers an overview of Bowser’s Star Reactor. Bowser’s Star Reactor is located in the Fountain dome and costs 15 stars to unlock. This is the boss galaxy of the Fountain dome, so you will receive a Grand Star for completing The Fiery Stronghold.
The Fiery Stronghold
This level has 4 areas. Your aim in this level is to defeat Bowser to grab the Grand Star!
Fire Bars - Fire Bars will rotate and will often be an obstacle that Mario will have to jump over or wait for them to pass. They inflict fire damage, which makes Mario jump around erratically - they’re especially dangerous when you’re on a narrow path!
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.
Boss Enemy - Bowser
Once you’ve reached Bowser on the tower, you’ll be transported to a small planet with a handful of blue domes on it. Bowser attacks in a few ways:
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.
Bowser will mix and match which of these attacks he will perform. You will want to get him to groundpound specifically on the blue domes though. So run up to him and guide him towards one of the many blue domes and then get him to groundpound it. Make sure you’re not standing on it though as it will smash and expose fiery lava.
This lava will damage Bowser causing him to run away from Mario. You will need to run around the planet in the opposite direction to catch him, as you won’t be able to chase him in the same direction he is running - he’s too fast! When you catch him, spin attack quickly to incapacitate him. This will cause him to spin around the island in his shell. Do the same thing as before and run the opposite direction to where he is headed so you catch him on his path. Spin him again to damage him. If you don’t catch him in time during either of these phases, you will have to repeat the process again.
You’ll need to perform this series of actions two more times, for a total of three lots of damage. Each time, he will become more aggressive in his attacks by spitting out more fire balls, creating more electric waves and groundpounding faster. He will also run away and spin in his shell faster, making it trickier to catch him. On the third and final phase of the fight, you will need to spin attack his spinning shell form twice in order to finish the boss fight.