Luigi’s Mansion 3’s B2 Boilerworks has six hidden gems shaped like wrenches. In this guide, we’ll show you their map locations and how to find them all throughout the level.
On every floor, gems appear in the same order from left to right in the menu: clear, red, blue, green, purple, and finally yellow.
However, you can’t get the clear gem until you make your way to 12F, at which point you will have to momentarily backtrack through B2’s Boilerworks. We’ve placed the clear gem at the end of this list to avoid spoilers.
Table of contents
- B2 Storage Room [Red gem]
- B2 Observation [Blue gem]
- B2 Sewer B [Green gem]
- B2 Sewer C [Purple gem]
- B2 Waterworks [Yellow gem]
- B2 Old Reservoir [Clear gem]
B2 STORAGE ROOM [RED GEM]
In the Storage Room, you start off in a small closet with one Gooigi pipe. The first one you see leads Gooigi to a dead end. Use your plunger to flip the bucket in that room to reveal a second pipe for Gooigi (1).
After going through it, you’ll reveal a larger room with water coming out of a pipe. As Luigi, suck air toward the crank in that room to reverse the flow of water, giving Gooigi access to the chest in that room and another pipe (2).
Take that new pipe to that room’s lower level, which will give you access to the B2 red gem — but first Luigi needs to reverse the flow of water again by blowing air at the crank to spin it the other way.
B2 OBSERVATION [BLUE GEM]
Find the coffee maker on the north side of the room. If you flash it, it will only drip once into its pot.
On the south end of the room, there’s an empty burner. Use your Dark-Light to make an extra pot appear.
Once you’ve revealed the pot, go back to the machinery at the north of the room. Flash it again, which will make brew a full pot that boils over, frying the machinery and making the blue gem appear.
B2 SEWER B [GREEN GEM]
Once you’ve lowered the water level, head all the way back through the sewer you floated through, and make your way to the end of the Sewer B section.
Place Luigi or Gooigi on the platform at the end of the tunnel, and switch to the other character to suck and pull on this metal knob here. This will raise the platform up, allowing the other to suck air at the gem, and eventually shaking it loose from the chain where the character down below can grab it.
B2 SEWER C [PURPLE GEM]
After you lower the water, go back up the ladder to the far right so you can go down the tunnel where you were chased by the shark ghosts in Sewer C.
Defeat them by pressing ZL+ZR to blast out a gust of air that will knock them off their shark outfits.
Once defeated, find the pipe in the center of the tunnel. Remove its lid by shooting a suction cup at it and ripping it off.
Have Gooigi enter the pipe, and you’ll find yourself inside a submarine. Grab the flaming canister on the left by sucking it up and bring it to the pot of fish stew on the right.
Light up the wood below it to get the pot boiling, and out will pop the purple gem.
B2 WATERWORKS [YELLOW GEM]
After you meet the B2 boss ghost, you’ll need to grab the key to enter the Boilerworks. To access the pipe that gets you to the key, suck up the hanging curtain that looks like a piece of the wall between the two pipes in that area. Doing so will reveal a third pipe in that area. Take that pipe upward, and Gooigi can make his way up to where the key is.
Once you grab the key, you can actually stay on that platform and walk all the way to the left to grab the gem.
B2 OLD RESERVOIR [CLEAR GEM]
Before you can explore 12F, you’ll be sent back to B2 to rescue Toad. To help him, you have to go through a bit of backtracking through Boilerworks into a new section leading all the way back to the Old Reservoir.
Once you’re at the very end of the Old Reservoir and ready to exit, keep an eye out for the wall with paint cans near it. Grab a few paints cans with your vacuum, and shoot them at the vague outline of a ghost. Once the area is covered in paint, a gem ghost will appear. Defeat it to get the final gem in B2.