This potion of the Luigi's Mansion 3 Guide includes the Master Suites Walkthrough and boss guides for defeating Hellen Gravely and King Boo himself. Every gem location is included.
Below are the walkthrough sections and objectives.Please note we may have added a few objectives ourselves to indicate the steps you need to take to complete the main objective.
- Find the Hotel Owner
- Collect all 4 Keys to open the doors
- How to beat Hellen Gravely
- Follow Mario
- How to beat King Boo
Master Suites Gems
Every Master Suites Gem can be collected on your first visit.Allgem locationswill be written in a blue box so scroll through for them to see what you're missing or scroll past them if you'd rather discover the answer to those puzzles yourself.
Take the elevator to 15F.
Move the projector screen
To get out of this area you'll need to move the projector screen. Start by heading to the right of the screen and pulling the vent cover off. Send Gooigi inside. Have him go through the next pipe and vacuum/hold the chain. Then, have Gooigi walk off the edge to the left so his weight will pull the chain until the projector screen is completely lifted (a green light will go off to indicate this as well).
Now that you're in the hall, you'll need to collect 4 keys to reach the hotel owner.
Get the gold key in the library
Head to the left of the hall.
When you reach the end of the hall, walk forward and take the door on the right. Watch out for Trapper blocking the door.
Now you're in the library. Use burst to blow the powder on the floor into the air and reveal the lasers. Watch the pattern of the lasers and walk past each set until you're downstairs.
Once downstairs, stand in front of the lasers and shoot the power box ahead. When the field is clear. Run up to that power box and pull on the rope. This will kill all the lasers and let you return to the top and grab the key.
Once you have the key, exit the room.
Be ready for a lot of tough ghosts waiting for you. Mostly watch out not to get hit with garbage thrown your way.
Get the green key in the drawing room
Head to the right side of the hall. Check your map for where that door is located. You'll have to shine your Dark Light to actually reveal the door.
Go inside and you'll be in the drawing-room: a cozy area with a fireplace and several sofas. Walk to the far left (near the front) and you'll see a painting with some windmill blades attached to it. Spin the blades to reveal a secret. But be careful! Everything is actually protected by lasers so spin the blades until you see a power box in a little cage.
When you do flip the room back to its "regular setting" and have Luigi or Gooigi stand by the fireplace. Then rotate the windmill blade to bring back the power box. Once the box is visible have the person standing by the fire just walk into that cage and flip the switch.
With the lasers turned off, rotate the room so the key is visible then just walk up and grab it.
Exit the room and move forward and to the left. Look for the large sheet of Hellen Gravely and Boo together. Vacuum it off the wall and use the Dark Light to reveal the door to the master bedroom.
Get the purple key in the master bedroom
Enter the master bedroom. Walk to the left and vacuum the dress off the mannequin bust. Suction shot it and pull it like a lever. Do the same on the mannequin on the right. Avoid the laser by walking up against the creepily circular bed.
Now you need to reach the power switch to turn off the lasers, then reach the key.
The platform moves based on where you're standing and it's powered by the green and purple switches. Make sure not to stand too far on one side. Keep it as steady as you can and power it up as fast as you can. The swinging of the platform will block some of the side lasers.
Keep going up until you're a little above the power switch on the right. You want to have time to run over there without falling.Turn off the power switch. Repeat the steps to reach the key. Then exit the room.
Walk down to the right and you'll have to fight a hall of ghosts. Remember you can take 2 at a time and slam them into each other.
Notice the Boo statue with the key slots. Walk towards it but before getting there take a right. Use your Dark Light to reveal a door to the Master Bathroom. Use your map for an extra hint on the door's locations.
Get the blue key in the bathroom
Watch out for the lasers which will appear shortly after you enter. Jump over them with the burst move.
Once you pass the shower use the burst move to see the lasers. Then slowly walk and jump with burst over the lasers as needed.
Turn off the power switch using the suction shot.
Walk to the right, near the tub, and vacuum so the faucet turns on and fills the tub to reveal the final key,
Place the keys into the boo statue
Finally, exit the master bathroom and approach the boo statue. Fight the hallway of ghosts, keeping an eye out for lasers you need to jump over with burst.
Hellen will float around on the top level (there's a bottom maze Gooigi can access through the drains on the floor) and come after Luigi. She carries a mirror that she uses to deflect your flashlight beam. When she gets close, she will try to hit Luigi -- evade her attack and her mirror gets stuck in the floor. This will allow you to stun her with your flashlight. However, when the force field shields are active and rotating on the top floor, trying to vacuum her up will just result in you getting hurt. So your mission is to turn off at least one (ideally two) of the barrier beams to get enough room to vacuum her up.
There are also red lasers that damage Luigi. For the single laser, just jump over it with the burst. The device in the center of the room will then create the four deadly shields.
Have Gooigi destroy the laser panels
To destroy her laser panels, send Gooigi down the drain (there are two in the room and green pipes in the wall to help him get where he needs to go.
When Gooigi is underground he can vacuum the fan blades out of the way by doing a burst jump or blowing them away (ZL) or vacuuming them up (ZR). The rounded power switches require a suction shot, the others just need to be walked up to and turned off.
Clear 1-4 of these panels and when you feel confident you can pull it off, stun Helen as Luigi and vacuum/slam her. You want to make sure you have space to do this so this means either none of her panels are active OR they're far enough away that you know you won't get dragged into them. Leave Googi on the bottom floor this entire time. You'll need to repeat this process a few times.
Repeat this process until Hellen is defeated. Note: sometimes her red laser will be more 1 or 3 lasers tall. When this is the case run away from them by getting close to the laser pillar. Hellen has some other surprises, namely a flood of water she sends to the bottom maze to destroy Googi, so just create a new one and send it down there again. Note: while Gooigi is trying to turn the panels off, Hellen may come after you. Don't try to stun her, as that will start the laser cycle. Simply do a Burst Jump with Luigi when she gets close and she'll leave Luigi alone for a while.
Once Hellen Gravely is gone, shine your Dark Light on the Mario painting to bring him back.
Once you go and follow Mario you won't be able to return to the lab so buy any Gold Bones now if you want them (don't worry though. You can reload your save to this part if you change your mind).
Follow Mario up the stairs and outside to the roof.
Mario is insane and clearly much more talented than you, so you'll need to walk around the building to the right to find a ladder you can climb to the top. Go past the King Boo statue and climb this series of ladders and stairs to the top. Release Peach from her painting with the dark light.
The battle against King Boo is a tough one. Here are all the moves you can expect and how to deal with them.
Wave 1 - Single Boo
Electric floor
Watch out for when the floor glows purple. Run to clear panels to avoid the electricity.
Tongue slam and swingWatch out for Boo's tongue which will come smashing down above you. After a few thrashes he'll turn back and swing his tongue. Jump early to avoid it (using burst).
Fireballs
Avoid the fireballs by walking/running between them.
Spiked ball with bombs
This is your chance to attack. The spiked ball with bounce and open to reveal some bombs (watch out for the active ones about to explode - those are red). Vacuum up a bomb and shoot it into Boo's mouth. He'll cough and fall to the ground with his tongue out. Have both Luigi and Gooigi vacuum the tongue. Then press A when prompted to slam him about.
Wave 2 - Find the real king boo
After getting hit once, Boo will form a mirror image of himself. Both boos can hurt you but only one boo is the real one.
Most of the attacks are the same but there's 1 new one (Slam) and tongue swing was replaced with tongue swirl.
Fireballs
Avoid the fireballs by walking/running between them.
SlamThe boos will try to drop onto you from above. Watch for the shadows and avoid them. Keep an eye on the landings because one boo will let out a shock wave that you'll need to jump over using Burst.
Tongue Swirl
After doing tongue slam the Boos will swirl their tongues around while moving left/right. You'll want to be close to the tongue and pick a time to run under it like a jump rope.
Only the real king boo makes a shockwave and only his spiked ball will be filled with bombs.
Vacuum up a bomb and shoot it into the real Boo's mouth. He'll cough and fall to the ground with his tongue out. Have both Luigi and Gooigi vacuum the tongue. Then press A when prompted to slam him about.
Wave 3 - Triple Boos (timed!)
Finally, there will be three boos on screen but only one is real. All the attacks are the same as wave 2 but this time things start with bombs falling in overwhelming clusters from above.
Vacuum up a bomb and shoot it into the real Boo's mouth. He'll cough and fall to the ground with his tongue out. Have both Luigi and Gooigi vacuum the tongue. Then press A when prompted to slam him about for the final blow.
Related Pages
- Complete Guide and Walkthrough
- Tips and Tricks
- All Gem Locations
- All Boo Locations
Janet Garcia is an editor and strategy guide writer at IGN. She has played both Luigi's Mansion, Luigi's Mansion Dark Moon, and now Luigi's Mansion 3. Afterspeaking to Nintendo representatives about Luigi's Mansion 3 at E3 2019and doingextensive research on Gooigi, she felt more than ready to take on every floor of this hotel. For more haunted content, you can follow her onTwitter @Gameonysus.
Additional edits and images by Aiden Strawhun. Follow them on Twitter @AStraww.
