Pool Party, or B-4, is the fourth mission in the Haunted Towers from Luigi's Mansion: Dark Moon. This mission is focused on Luigi arriving to the Rooftop Pool to investigate the action that was happening when Luigi and Professor E. Gadd scrutinized the snapshot the Toad took.
Before this mission starts, Luigi and Professor E. Gadd takes a look at the photo the Toad takes. Professor E. Gadd notices a Boo and a Sneaker handling the special key: the key that is required to open the door in the Hollow Tree. They see other significant events in the picture: two Boos are handling a suspicious portrait, the Boos encouraging the behavior, and the Sneaker, a ghost they have not seen yet.
Luigi has to go to the Rooftop Pool to investigate. When he reaches the Courtyard, he notices two Flytraps inhabiting the area. Luigi has to run left and dash all the way in order to not get attacked by a Flytrap. He then should go to the Tower Lobby and continue to the Plant Nursery, where he notices a plant. Luigi should then activate the water by turning the wheel in the right of the room. Luigi, after the water is activated, should carry the bucket of water to the water source and water the plant. This makes the plant grow, enabling Luigi to access the room above him: the Rumpus Room.
In the Rumpus Room, Luigi should go to the dollhouse and inspect it. Upon inspecting it, Luigi sees a reflection of the room, and which box is shaking so he can open it. The shaking box has several Greenies inside it; opening it reveals them. After capturing all Greenies, the room brightens and Luigi can leave the Rumpus Room and enter the Family Room. After the Family Room is the Solarium. To climb up the stairs, Luigi must pull a cord near the stairs to straighten. Luigi can then reach the West Bedroom.
To get access to the next room, Luigi must blow on a ceiling fan to reveal more of the bedrooms. In there, three Hiders are having a pillow fight; upon taking sight of Luigi, they flee into the beds. Luigi has to pull the blankets off one bed to reveal a Hider. After Luigi sucks in the Hider, the other two Hiders shuffle the beds. Luigi has to repeat the processing of revealing the Hiders so that the key to the West Hall appears.
Luigi cannot access the door north in the West Hall. He has to go through the Crow's Nest and into the Conservatory. In the Conservatory, Luigi must suck in the Bulb in order to fly to the second floor, where a door to the Crow's Nest is available. In that area, Luigi finds a key in a painting: shining the Dark-Light Device onto this painting gives him the key to the West Bathroom, the room located north in the West Hall.
When Luigi enters the West Bathroom, a Slammer is found inspecting itself in the mirror. Confronting the Slammer reveals two Greenies, one sporting sunglasses. Luigi also has to defeat a Creeper found on the right area of the room. After all these ghosts are defeated, Luigi can then access the Rooftop Pool by lying on the chair north of the room. In the Rooftop Pool, Luigi has to use the Dark-Light Device and suck up all the Spirit Balls to reveal a hidden frog statue. The hidden frog statue spits out the special key; when Luigi tries to grab it however, Sneakers steal it. Defeating all Sneakers reveals the hidden key, but a Polterpup snatches the key and accidentally drops it out the window. Professor E. Gadd learns of this and transports Luigi back to the Bunker.
The Toad you rescued in the Crypt managed to bring back a snap shot from my tridimensional security camera! Let's take a look at it.
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