Luigi’s Mansion 3: B2 Boilerworks Guide

Featured image on B2 Boilerworks Guide

After you’ve made your way through the Unnatural Museum you will receive the Elevator Button for B2, a floor below the basement. On this floor you will find the guts of the Last Resort. To help you navigate this floor use the B2 Boilerworks guide below.

Note: you can find a guide to the gem locations on this floor here.

How to Get the Key in Boilerworks?

Image showing how to get the Boilerworks Elevator Hall key.

Make your way from the elevator and head to the right. As you transition between screens you will trigger a cutscene with the boss of this area called Clem. The boss will turn on some water then disappear. Vacuum the valve on the pipe above to turn off the water then vacuum the tapestry on the middle of the wall to reveal a pipe. Send Gooigi through the pipe to get the key. Open the door and enter the Waterworks.

How to Catch and Defeat the Mechanic Ghost Clem?

Once you’ve unlocked the door you will get a new objective to Catch and Defeat the Mechanic Ghost. This can be done by reaching the final room of the Boilerworks. To do this you will complete a number of puzzles across the different rooms of the floor. To learn how to solve each puzzle I’ve highlighted them below.

Waterworks Puzzle

Image showing how to solve the Waterworks Valve puzzle.

The first room you enter is called Waterworks. In this room there are a couple of ghosts to defeat. Do this then send Gooigi down the pipe in the right corner of the room. With Gooigi in place below, use Luigi to manipulate the three valves topside to get him to the switch on the far right corner. The proper valve order is:

  1. All valves right.
  2. Walk Luigi to under far right spout.
  3. Far right valve left.
  4. Walk Luigi to under one spout right.
  5. All valves left.

Follow the sequence above to get allow Gooigi to reach the switch. Use your Flashlight on the switch to open the door above. Switch back to Luigi and head through the door into the Reservoir.

Reservoir Room

Image showing the Reservoir Room.

In the Reservoir room there is a platform in the middle of the room you can control using the generator at the bottom of the room. Put Gooigi next to the generator and place Luigi on the moving platform. Suck the generator with Gooigi and it will move allowing Luigi to access the ladder leading to the closed door on the far wall. Walk up to the door to trigger a cutscene. After the cutscene head to through the door on the right into the Observation room.

Observation Room

There’s not much of interest inside the Observation Room. Make your way through the room and head into the room to the right which is the Sewer A room.

Sewer A Room

Image showing the Sewer A room.

Inside the Sewer A Room make your way down the ladder and jump onto the ducky floaty. Navigate the floaty over to the ledge with the pipe on it. Send Gooigi through the pipe and he will emerge on the ledge above. Walk to the pipe to the left and go inside it. You will emerge on the right side of the water. Pull the orange ball and switch to Luigi. Use the duck to travel right through the now open gate.

In the next section of the room do the same thing with Gooigi, but use the valve below to cut the water off so Gooigi can pass over to the orange ball. Pull on the orange ball to open the gate and send Luigi through again. Walk Gooigi to the right and go inside the pipe there.

Sewer B Room

Luigi will being to quickly float towards the gate at the end. This gate has spikes on it. Send Gooigi through the different pipes until he reaches the orange ball and open it to let Luigi through. You will end up in Sewer C Room.

Sewer C Room

Image showing Sewer C room.

In Sewer C Room you will begin to float towards another gate. Go towards the ledge and summon Gooigi. Send Gooigi through the left pipe and walk him to the left. You need to avoid the water hazards here by timing your movement under the pipes. While you are moving Gooigi you want to get Luigi moving in the water.

Once you reach the pipe that is closed with Gooigi, take control of Luigi and move him over to the orange ball. Use the orange ball to open the pipe allow Gooigi through. Avoid the water with Gooigi as you walk to the left until you reach the orange ball that opens the gate. When the gates open shark ghosts will appear. Avoid them and make your way through the gate into the Drainage Control room.

Drainage Control Room

Image showing the Drainage Control Room sequence.

When you enter the Drainage Control Room you should make your way to the ledge. Get off the ducky and walk into the water. This triggers a cutscene and ghosts will attack you. Defeat the ghosts then head to the left and you will find a pipe there. To reach the Drainage Control you need to use the valves to send Gooigi up to the platform above. Use Luigi to turn the valves. Note you need to move the middle valve to the left to send Gooigi up to the ledge to interact with the far right valve. Return to the Reservoir Room via the Sewer.

Resevoir Room

Make your way over to the door we attempted to enter earlier and open it using your Vacuum. Go inside the door to trigger a cutscene. You ready for a boss fight?

How to Defeat the Mechanic Ghost Clem?

Image showing how to defeat Clem.

This fight is simple but a major pain to complete as the controls are inverted. Luigi rides around on a floating Ducky while fighting the boss. To defeat the boss you want to use the mines the boss deploys against him to cause him to spin out. To do this trigger a mine when he is near then float away. When the mine explodes the boss will spin out. When the boss is spinning out vacuum him up and throw him into the spikes on the inside of the ring. This causes the ghost to end up on the upper level. On the upper level you can deal damage to him like a normal ghost.

To make things easier on yourself deploy Gooigi on the upper level and use Gooigi to damage him when he’s up there. Repeat the process until the boss is defeated. Upon defeat of the boss drain the pool and grab the Elevator Button 10. Return to the elevator and insert the button. Head to 10F to start the next area called Tomb Suites.

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