Luigi losing coins

Luigi after he has opened a Fake Door in Luigi's Mansion.

Fake Doors (or Trapdoors) are a special type of doors appear in Luigi's Mansion and Luigi's Mansion 2. In Luigi's Mansion, if Luigi attempts to open one it will quickly swing into him flattening him against the wall. This causes the green clad plumber to drop coins and lose 10 of his HP. However, there are a few ways to find out if a door is fake. Firstly, the player has to press "Y" to look at the map. They will notice that Fake Doors don't appear. This is a clue to avoid them. A secondary way is to look below a door to see if there's a mat. If the door does not have a mat, it's fake. However, some doors such as the one that leads to the Laundry Room do not have a mat, so it might be easier to look at the map. Another way is if Luigi happens to walk past a door that is fake, he then looks at it for a brief second, revealing that it's fake. Luigi will not look at a door that is real. Also, most Fake Doors appear on the wall furthest away from the TV screen. Lastly, if Luigi uses his vacuum on a door that's not fake, it will shake and rumble. Fake Doors are unable to do this.

There is a way for Luigi to eliminate a Fake Door, by simply sucking up a Fire Elemental Ghost and use it to burn a Fake Door. After that, the Fake Door will disappear. However, if Luigi enters two different rooms, including hallway corridors, the door will reappear. It should be noted that during the blackout, the number of Fake Doors have increased in more areas, as well as areas that had Fake Doors even before the blackout.

Using the Fire Element, you can also cause a glitch in the game. Where if the door vanishes as it's being burned and you press "A" quickly enough, an invisible door will flatten him. This is because the game doesn't expect you to do that and figures that the door is still there for that moment.

If the damage of a Fake Door causes a Game Over, the game won't have enough time to display Luigi's death animation, because the animation of Luigi being flattened and getting up again takes too long.

In Luigi's Mansion: Dark Moon, Fake Doors give Luigi the same fate as in the first game; slamming him against the wall multiple times. However, in this game Fake Doors will only make Luigi lose 5 HP. There is no way, save for the map, to tell a Fake Door apart from a real door, and since there is no Fire Elementals, there is no way to get rid of them either. On the map, they will not be shown, indicating that the door is fake.