Luigi’s Mansion 3 King Boo Boss Fight Walkthrough

Luigi’s Mansion 3 King Boo Boss Fight Walkthrough

Here’s how to defeat King Boo in Luigi’s Mansion 3.

Luigi’s Mansion 3 culminates in a rooftop boss battle with King Boo. It’s a really tough fight, and you’ll need to use everything you’ve learned so far to beat them. To help you out, we’ve put together this King Boo Boss Fight Walkthrough. We’ll give you some tips on how to prepare, and detail the phases you’ll be up against.

How to Beat King Boo

First off, we recommend you stock up on Gold Bones from the Shopping Network. Three should be fine, though feel free to add a fourth if you have the money spare. The first attacks you will be up against are the following:

  • Lightning Strike: Purple squares will appear all over the ground, stand in the empty space to avoid getting hit.
  • Fire Balls: King Boo will spit fire balls out at you. These are easy to dodge.
  • Tongue Slam: King Boo will slam his tongue down three times, and then swing it across the stage. Use the jump to avoid the final swing.
  • AoE Slam: King Boo will slam down on the area indicated by a shadow. A shockwave will appear, use jump to clear it.
  • Spiked Bomb Ball: Finally, he will throw a purple ball down, revealing bombs

Make your way through the first four attacks, until you see the bombs come out. Pick up a bomb that IS NOT flashing red. You can then fire it into King Boo’s mouth as it opens. Once he is down, you’ll need to use Luigi AND Gooigi to vacuum his tongue. Tap A to slam him down. Now, onto the next phase, two King Boos will spawn. This is where the fight gets a little harder. They will use the same attacks as before, though at the end of the third tongue slam they will move their tongues across the stage. You will need to time your run to get underneath them. To damage King Boo, you’ll need to work out which is the real one, which we’ll cover next.

How to Find the Real King Boo

To damage King Boo, you need to work out which is the real one. There are two ways to do this. When they slam down onto the stage, only the real one will produce a shockwave. Another indication is that only the real King Boo will produce bombs out of the spiked ball they throw, the fake is filled with spiders.

Now Fight Three King Boos

Now there are three King Boos and the fight is largely the same. The only difference here is that they will start by enveloping the area in bombs. You cannot fire these back so just outrun them. Cycle through the attacks as before and use the clues described previously to find the real Boo. A timer will appear in this phase, though you will have plenty of time to clear the fight so don’t worry Fire a bomb into its mouth and the fight is over.

Use the Spiders For Health

The best tip we can give you for this fight is to use the spiders to your advantage. Once two King Boos have spawned, they’ll be thrown out fairly regularly. Flash them to get some health back if you need.

That’s how to beat King Boo in Luigi’s Mansion 3. For more on the game why not check out our locations for all of the gems. Elsewhere there’s also our look at earning Gold.

Jake Green

Senior Guides Writer

Jake is a former freelance writer who is still very much new to all of this. He spends his days dreaming of an X-Files dating-sim and playing wonderfully silly VR games. He has an unhealthy obsession with Mega Man, and would pretty much trade a kidney for Skate 4 at this point.

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