Luigi’s Mansion 3: 15F Master Suite Guide

Featured image on 15F Master Suite Guide

The top floor of the Last Resort hotel is home to the Master Suites. This floor houses the owner of the hotel. It also leads to a final showdown with King Boo on the top of the hotel. To make your way through this final floor and the end of the game use the 15F Master Suites guide below.

Other Master Suites Guides:

Reach Hotel Owner

Image showing how to move the movie screen in the lounge.

From the elevator walk to the right to trigger a cutscene with the owner of the hotel. After this cutscene you walk to the right corner next to the screen. Plunger the cover off the pipe there and send Gooigi into the pipe. Go through the pipe in the room up to the chain. Suck up the chain and walk off the ledge to raise the screen. This reveals doors. Go through them as Luigi to reach the Hallway.

Key 1: Library

Image showing the key in the Library.

Inside the Hallway there are four rooms you can enter. The first room we want to enter is the Library. The Library is the bottom left room. Go inside and make your way past the lasers (use jump to reveal them) to the bottom of the room. Plunger the fuse box to turn off the laser and go back upstairs to grab the key. Return to the Hallway.

Key 2: Drawing Room

Image showing the key location inside the Drawing Room.

Make your way through the Hallway to the right corner. Use your Dark Light to reveal a door leading to the Drawing Room. Go through the door into the room. Walk to the left and you will find a windmill on a painting. Summon Gooigi and make him stand by the fireplace. Switch to Luigi and spin the windmill until the fuse box appears. Walk Gooigi into the fuse are and turn it off. Turn the windmill until the key appears and grab it.

Key 3: Master Bathroom

Image showing the key location in the Master Bathroom.

Head down the Hallway to the next group of rooms. Go into the room on the right by revealing the door with the Dark Light. Inside the Master Bathroom make your way through the room, avoid the lasers, until you reach the fuse box. Turn the power off then head into the tub and turn it on by blowing the faucet. Grab the key.

Key 4: Master Bedroom

Image showing the location of the key in the Master Bedroom.

To the left of the Master Bathroom you will find the Master Bedroom. To get inside this room reveal the door using your Dark Light. Go inside the door. Walk over to the mannequin to the right of the bed and Plunger it. This causes the the floor to rotate. Get on the seesaw and use Gooigi and Luigi to weight it so you can reach the fuse box. Turn off the fuse then reverse the seesaw so you can reach the key.

Open Boo Door

Image showing the open Boo door.

Once you have all four keys make your way to the Hallway and head to the large Boo head to the north. As you head towards the Boo door you will be attacked by ghosts. Take them all out and continue to the door. Open the door and head inside to face off against the Hellen Gravely.

How to Defeat Hellen Gravely

Image showing how to defeat Hellen Gravely.

The fight with Hellen Gravely can be a bit of a pain. It is fairly straightforward to complete, but it can quickly get away from you if you aren’t ready. To take out this ghost you need to do the following:

  1. Avoid lasers when Hellen is on the screens. When Hellen is on the screen she will trigger laser beams you need to avoid by running from them or jumping over them.
  2. Once Hellen is on the ground four barriers appear in an x pattern. To avoid the barriers you need to send Gooigi down the drains on the corners of the room. In the crawlspace below there are colored fuses to turn off. Switch between Luigi and Gooigi to avoid taking damage.
  3. During the barrier phase Hellen will attack you. You need to dodge her attack then hit her with the flashlight. This allows you to deal damage.
  4. Repeat until dead.

Once you’ve defeated Hellen Gravely aim up at the portrait of Mario and use your Dark Light to free him. Mario will open a secret door and will run through the door. You may want to grab some resurrections before the fight. Follow him to reach the top of the hotel. Here you will fight King Boo.

How to Defeat King Boo

Image showing How to Defeat King Boo.

On the roof of the hotel you will encounter the King Boo. This starts the final boss fight. To defeat King Boo you need complete three rounds of the fight. Each round follows a similar pattern which involves dodging King Boos attacks until he launches spiked balls that break to reveal bombs. Shoot these bombs into King Boo’s mouth. Each round you complete there is another Boo. The final round has you fighting three Boos.

Upon defeat of King Boo you will complete Luigi’s Mansion 3. Enjoy the cutscene which shows you and the ghosts working together to rebuild the hotel.

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