Luigi's Mansion 4: The Lone Ghost

Plot
One day, Luigi received a letter. The letter was sent by Hellen Gravely, the owner of a cruise ship that crosses the seas. When Luigi opened it, he discovered that it was a special invitation! "''Congratulations, Luigi! You are the lucky winner of a free stay at a world-class resort cruise, The Final Destination. We look forward to dazzling you with first-rate hospitality and service. Please be sure to invite any friends or family you'd like to bring!" -Hellen Gravely'' Luigi was overcome with excitement at the letter and rushed to go on the cruise alone. Soon, he departed for the cruise ship.

Upon arriving at the harbor, Luigi was strangely warmly welcomed by Hellen Gravely herself! Afterward, he was shown to his rooms. Luigi notices a locker room that has two lockers in it. Each locker holds the Poltergust G-00 and the Poltergust 3000. Little did he realize it was all a trap by Hellen Gravely to revive the God of the Mirrors, Leinth. Awakened in the night by the evil laugh of Hellen Gravely and King Boo, Luigi found a hotel swarming with ghosts and demons. Not only that, but the toads who got on the cruise ship in secret have all been sealed away, and it turns out the lockers that hold the Poltergust G-00 and the Poltergust 3000 have been broken. Will Luigi be able to rescue his trapped friends and escape the cruise ship in one piece, or will they be stuck on the boat sailing the haunted seas forever

Luigi
Luigi is a heroic, kind, and sensitive character. Luigi is optimistic, cheerful, quiet, and kind-hearted, like his brother. Still, unlike Mario is most shy, fearful, and can be goofy and naive at times, Luigi aspires to be like his brother Mario and become the hero of the Mushroom Kingdom. However, during the nightmare sequence, Mario ignores him when he gets the award for Mushroom Kingdom Hero. Luigi did not get a medal, either. To make matters worse, Mario and his friends make fun of Luigi and proceed to Laugh at him. Mario ignores him and even pushes him down the stairs whenever he goes downstairs and during "Super Mario levels."

Gooigi
Gooigi reappears in Luigi's Mansion 4, where the player can use him to reach certain areas that Luigi cannot reach, such as areas behind bars, past spikes, or through grates. However, he melts if he touches water and disintegrates if he touches fire. Gooigi is unable to open doors, although he can still insert keys in them to unlock them. Gooigi can also vibrate when Luigi is near a door and enters a room where a Boo is hidden; the closer Luigi is to the Boo, the more Gooigi vibrates.

Gameplay
Luigi's Mansion 4, plays much like the three previous entries in the series, returning to a singular setting much like the first game while featuring a variety of themed rooms akin to the second game's cruiseship, allowing the player to re-explore already completed rooms. The Poltergust 3000 retains the basic qualities of the two previous vacuums, as well as the Strobulb item and the Dark-Light Device,

ScareScraper
Like its direct predecessors, ScareScraper also returns, allowing for up to twelve-player co-op multiplayer (via six Luigis and six Gooigis) to clear either 5, 10, 15, or 20 or a random amount of floors between one to twelve, with a one, three or five minute time limit for each floor, except the Rooftop, which has a time limit of roughly two, six or ten minutes. The mode also features procedurally generated floors, with different challenges on each floor such as Capture the Ghosts!, Find the Toads!, and Collect the Money!. It acts very similar to its prequel appearance, though adds new abilities and functions such as the super suction, super strobe, a red siren trapdoor detector helmet, voice chat, and the Blackout.

Little Carnival
A multiplayer party mode where two teams called Team Luigi and Team Gooigi consisting of Luigis and Gooigis respectively, set to compete against each other in over 12 minigames.

Overview Trailer

 * Announcer: Luigi's most haunting adventure is finally here, and this time, his biggest enemy is...."Himself"
 * Announcer: You will see why in...Luigi's Mansion 4: The Lone Ghost
 * Announcer: Luigi, his brother Mario and his friends have been invited to come on a cruise.
 * Announcer: With all the right company, what would possibly go wrong?
 * Announcer: Luigi's nightmare was, unlike anything he had ever seen before. The ghosts from his nightmare have fled from his head, in his bed. He Should've stayed home instead.
 * Announcer: The only way to eliminate these ghosts is with Professor E-Gadd's new invention. Behold, the Poltergust 3000.
 * Announcer: Vaccum ghosts, freeze them, let out some air, or pull something out of thin air.
 * Announcer: The Slam. Any ghosts you happen to be vacuuming cam also be slammed for Extra Damage. Slam one ghost into another, to help them "move on".
 * Announcer: Or slam ghost into another, suck them, and destroy them, to bring them into..."Self Condemnation". Mua ha ha ha ha ha ha ha.
 * Announcer: Oh yes, the suction cup. I see it now. Simply aim and fire and launch on to a target.
 * Announcer: I know it can "suck" sometimes, but you don't need to tell me
 * Announcer: Some ghosts are more "Bossier" than others.
 * Announcer: Queen McJoust, isn't afraid to attack poor Luigi
 * Announcer: His face does not look ready to Captain Starscream
 * Announcer: But...Luigi has to face his biggest boss yet....himself
 * Announcer: Does Luigi....deserve...to be rejected? Do his friends "really" love him?
 * Announcer: What do you do to ignore the ghost behind you? Do you follow your instincts blindly?
 * Announcer: Do you hide yourself from these bad dreams and give in to sad thoughts that are maddening?
 * Announcer: Do you sit here and try to stand it or do you try to catch them red-handed?
 * Announcer: Do you trust some and get fooled by phoniness or do you trust nobody and live in loneliness?
 * Announcer: Luigi's latest adventure will be decided by you.
 * Announcer: Now you can't go on a cruise without having a little...fun.
 * Announcer: Are you team Luigi or are you team "Gooigi"?
 * Announcer: Either way, up to eight competitors can face off on one system in "Little Carnival"
 * Announcer: Even Luigi deserves a little break, and these 12 minigames are just what he needs.
 * Announcer: Poor Scared Luigi, poor traumatized Luigi. Is he going to be okay?
 * Announcer: Oh he will be, because traveling on the high seas in a ghost-filled cruise ship, is "Boo-tiful"."
 * Announcer: Luigi's Mansion 4...The Lone Ghost, Available October 31st, 2025, only on Nintendo Switch Plus.