Luigi's Engine Room is the last of the six default stages in the game. It is owned by Luigi.
This is by far the hardest non-locked stage in the game. It has quite a few branches. Players start at the bottom right corner of the board.
The first branches both lead to the middle of the stage. The longer branch has a robot that will open the closed doors and close the open doors.
The middle branch leads three ways. To the left is Bowser, who will give you 1 coin for 20 coins. Beyond Bowser the path leads to a pipe that brings you to a Boo and the beginning.
The right path leads to another pipe that will also bring you to the beginning.
The upper path leads to either the right or the left, depending on which door is open. If the left door is open, you will be in a square and keep going around until the door leading to the pipe is opened or you stand on a happening space to escape.
The happening spaces do two things on this board: one opens and closes the red and blue doors and the other one brings you to a secret area that takes you back to the beginning.
At the end of the game, the winner's stars form into a large star that goes over to the engine and powers it up. It is revealed that the engine and surrounding board are located inside a wooden airship, with the winner standing at the front of the ship. The players in 2nd and 3rd place, Toad, Koopa, Boo and the star accompany them. While the player in 4th place stays in the engine room and is burnt by the steam generator, Bowser laughs at their torture.