''Luigi's Mansion''s story takes place over four "areas", or sets of explorable rooms between
boss fights. Players may also access a training room and a gallery at Professor E. Gadd's laboratory between areas or upon starting the game. In each area, players control
Luigi to explore the mansion's rooms and hunt down the ghosts within them, acquiring keys to get through locked doors and eventually fighting a boss ghost at the end of the area. To assist him in his task, Luigi uses a flashlight and two devices supplied by
E. Gadd – the Poltergust 3000, a specially modified, high-powered
vacuum cleaner; and the Game Boy Horror, a
mobile device designed after the
Game Boy Color. To capture ghosts, Luigi must first stun a ghost with his flashlight, revealing its heart. He then must use the Poltergust 3000 to suck them up, steadily reducing the ghost's hit points to zero, at which point they are captured. The more hit points the ghost has, the more time it takes for a ghost to be captured, giving them a chance to break free while leaving Luigi more exposed to harm. If Luigi's
health is reduced to zero from being hurt by the ghosts or other accidents, the game is over. Along his journey, Luigi locates three elemental medals, each granting the Poltergust with the ability to summon and vacuum ghosts from fire, water, and ice sources and expel their respective elements to capture specific ghosts or solve puzzles. In addition to capturing the regular ghosts in the mansion, Luigi must catch "portrait ghosts" from some rooms, each requiring a condition be met to make them available for capture. Rooms are usually dark upon initial access, and Luigi hums nervously to the music, but once all the ghosts are captured, it brightens up, and Luigi pleasantly whistles the melody. Using the Game Boy Horror's
mobile phone-like functionality, players can access a map of the mansion, seeing which rooms they have visited, what doors are open, and which remain locked. When Luigi finds a key during his explorations, the Game Boy Horror automatically indicates which door it unlocks. In addition to a map function, the device allows the player to examine objects (including the hearts of portrait ghosts, revealing clues about how to capture them), read profiles of captured portrait ghosts, and keep track of any treasure that Luigi has found. Rooms will usually have treasure hidden within, which can be either coins, bills, gold bars, pearls, or gems. The treasures are typically hidden inside objects as well as chests that appear when rooms are cleared, though they can also be found from vacuuming ghosts. Luigi can gather these treasures by walking into them or vacuuming them; if a ghost harms Luigi, he will drop a few coins that he will need to recover before they disappear. After Luigi encounters a group of
Boos hiding in the mansion, the Game Boy Horror can be used to find each one hiding in a room through a beeper sound and a flashing yellow light on the device, which turns red when Luigi is close to one. Boos can only be located in cleared rooms. at which point a result screen reveals the portrait ghosts Luigi has captured, along with the total amount of treasure he recovered for that stage. Once the final boss is defeated, the player is given a rank (A to H) after the end credits based on the amount of treasure Luigi has found. Completing the game once unlocks a second mode called the "Hidden Mansion", which features a stronger Poltergust and stronger ghosts. In the European and Australian version of this mode, the mansion appears as a mirrored reflection of the previous version, bosses are more difficult, ghosts and Portrait Ghosts are trickier to capture, and more ghosts appear in some of the rooms. Most of these Hidden Mansion differences were later added to the Nintendo 3DS remake of the game in all versions, although the stronger Poltergust and mirrored mansion were removed. ==Plot==