This page offers a walkthrough of Darkness on the Horizon found in Bowser’s Dark Matter Plant, which is the Boss level of the Bedroom dome. It requires 33 stars to unlock the galaxy.
Welcome to the Dark Matter Plant
In the starting section, you’ll be introduced to a few of the areas that will become more prominent and tricky later in the level.
Firstly, you’ll need to take the moving platforms from the starting area across the dark matter to the rotating tiles area. Later on, you’ll find yourself in a tricky challenge regarding the dark matter.
Next, you’ll need to cross the rotating platforms over to the gravity sections. Here, you’ll be reminded of how the gravity walls work. This section is straight forward enough, just jump across the platforms and keep an eye on the arrows on the walls than denote what direction the gravity is pulling you in.
In the next area you’ll need to climb up a pole that’s being circled by Goombas! You can either defeat them or jump onto the pole and work your way up.
Dark Matter Paths
In this next section, a Luma will warn you that there are holes in the path that will suck you into the dark matter below. If you’re caught in one of the holes, you’ll instantly lose a life and begin at the beginning of the dark matter section. Avoid the holes by jumping to the other platforms, then jumping back when it’s safe. Then, once you’re on solid ground again, you’ll need to walk a little before you come across some more paths across dark matter. Once again, watch out for the holes and utilise the both platforms to make your way to the safe path.
In this area, you’ll need to stand on the platforms in certain places to make sure you don’t fall into the Dark Matter. Below, you’ll find screenshots of where you should stand to make sure you don’t fall:
Free the Lumas
In this next area, spin attack the crystals to free the Lumas. When you free them, they’ll create stairs that you can use to reach the Boss fight. There is also an extra life mushroom that you can free from a crystal aswell. Definitely handy for the boss fight!
Bowser Boss Fight
This boss fight is very similar to the last boss fight in The Fiery Stronghold. He has the same attacks as listed below:
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.
In this fight, he also has a new attack called the Dark Spin attack. This is essentially a spin attack that will damage and push you back.
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.
When you defeat him, he will run away, leaving you with a Grand Star.