There are six collectible gems on each floor in Luigi’s Mansion 3. In this guide, I’ll show you where to find all six gems on the 13F floor and tell you how to get your hands on them. You’ll need to unlock certain abilities before you’ll be able to collect some of these gems, so you may have to come back later on in the game.
Please note that some of the gems will appear clear rather than coloured in the screenshots seen below, this is because I had already collected them during my playthrough before creating this guide.
Gem #1 – Elevator Hall
As soon as you come out of the elevator, stand on the circle in the middle of the room and you’ll see the cabinet on the right hand side of the room open slightly. Summon Gooigi to stand on the circle with you and the cabinet will open all the way, revealing the Yellow Gem in a glass case. Use your vacuum to suck it up and then fire the case into something to break out the gem.
Gem #2 – Gym Lobby
Head into the gym lobby and shine your Dark Light on the right hand side of the desk to make a bell appear. Walk away from it and it will ring three times, startling Luigi. Go over to it and Press X to ring it – perform this step three times and a ghost will appear. Defeat this ghost and it’ll drop the Clear Gem.
Gem #3 – Locker Room
Head to the left hand side of the locker room and go down the small set of stairs. On the back wall you’ll see a door with a swimming pool sign next to it. To the right of that swimming pool sign there’s a cabinet which is home to a big green boxing glove. Use your vacuum to suck up this boxing glove and fire it at the pool sign and it will open up and spit out the Blue Gem.
Gem #4 – Weight Room
In the Weight Room, head to the bottom left corner of the room to find a small set of steps leading to a raised platform. Go up here and run all the way to the right and stand on the scales with Luigi. Look at the mirror and you should see the reflection of a small hatch opening up in the far left pillar, revealing the Red Gem. Stay on the scales with Luigi and use Gooigi to run back down the small steps to vacuum up the gem.
Gem #5 – Training Room
Go into the Training Room and walk up the stereo at the top right of the room. Use your Strobulb on it three times until the spooky music plays and the room darkens, then go to the treadmills on the left side of the room to find three ghosts. Defeating the two on either side will earn you a whole wad of cash, but defeating the ghost on the middle treadmill will bag you the Purple Gem.
Gem #6 – Shower Room
Finally, go into the Shower Room and use Gooigi to slip through the grate in the middle of the room. Once in the room below, use your vacuum on the valve to drain all of the water, then drop off the platform to the right and through the grate to grab the Green Gem.
And that’s it! Congratulations, you collected all six gems.