Luigi's Engine Room is Luigi's board featured in Mario Party. It takes place in an engine room to an unknown place until the end. The engine in top center of the board doesn't have enough energy. So the mysterious thing that works with engine would not work properly.
If you visit Bowser, he would have a machine called "Make As Many Coins As You Want Mecha." He would turn on the machine and it will produce one coin for the player to keep. Then he'll charge the player 20 coins for the free coin.
After becoming the Superstar, the Stars will form into a huge Star and then it will attach itself to the engine, giving it all the energy it need. A scene will show that a winged airship was what the engine is powering and 1st place person will stand on the front of the ship while 2nd, 3rd place people and the supporting cast accompany them on the airship. The 4th place person stays in the engine room and is burnt by the steam generators while Bowser laughs at their torture.