The Dark-Light Device is one of E. Gadd's inventions and it is used by Luigi in Luigi's Mansion: Dark Moon.
Usage
The Dark-Light Device in action.
The Dark-Light Device is mainly used to uncover hidden or invisible objects. This can cast a rainbow-like light that can reveal enemies called Spirit Balls, which Luigi then can use the Poltergust 5000 to vacuum them up. The Dark-Light Device also helps in capturing Boos, find tracks leading to the Polterpup, and to aid in fight with certain ghosts (such as Sneakers). It can also reveal coins and even Toad Assistants in paintings Luigi first acquires the Lab of Gloomy Manor during the fourth mission A-4: Visual Tracks.
The Dark-Light Device can be used by holding the "Y" button. Be careful as if the gauge for the Dark-Light Device is used up, it will overheat and leave Luigi wide open to ghost attacks. The Dark-Light Device can be upgraded after Luigi has cleared a mission and has the necessary money.
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| Major characters | Major characters | Luigi • Mario • Professor E. Gadd • Toad • Polterpup • King Boo |
| Ghosts | Regular | Ancient Poltergeist • Boo • Creeper • Gobber • Greenie • Gold Greenie • Hider • Poltergeist • Polterpup • Slammer • Sneaker • Strong Gobber • Strong Greenie • Strong Hider • Strong Slammer • Strong Sneaker • The Three Sisters |
| Bosses | Story mode: Ancient Poltergeist • Big Boo • King Boo • Three Poltergeists • Possessors (Grouchy · Harsh · Overset · Shrewd · Tough) • A Strong Gobber, a Strong Greenie, and a Strong Slammer • Strong Poltergeist • The Three Sisters ScareScraper: Beetle Whisperer • Bomb Brother • The Brain • Creeper Launcher • Primordial Goo • Terrible Teleporter | |
| Other species and enemies | Bat • Beetle • Crow • False door • Flytrap • Frog • Fuzzball • Gold Robomb • Mouse • Orange flower • Robomb • Spider | |
| Locations | Gloomy Manor | Balcony • Bedroom • Cellar • Coatroom • Common Hall • Dining Room • Entrance • Foyer • Front Yard • Garage • Guard Hall • Kitchen • Lab • Library • Lobby • Master Hall • Mudroom • Mudroom Exterior • Parlor • Patio • Rafters • Secret Pocket • Studio • Study • Under the Stairs |
| Haunted Towers | Botany Lab • Conservatory • Courtyard • Crow's Nest • Crypt • East Hall • Eerie Staircase • Family Room • Garden • Gardener's Dwelling • Gardener's Lab • Greenhouse • Haunted Towers Entrance • Hollow Tree • Hydro Generator • Laboratories • Lounge • Old Graveyard • Plant Nursery • Rooftop Pool • Rumpus Room • Seedling Laboratory • Sewer • Skybridge • Solarium • Tool Shed • Toolshed Stairs • Tower Lobby • Tree House • Tree Root • Water Supply • West Bathroom • West Bedroom • West Garden • West Hall | |
| Old Clockworks | Antechamber • Belfry • Belfry Clock • Canyon Hall • Canyon Narrows • Canyon Stairs • Cargo Room • Clock Tower Gate • Clockmaker's Chambers • Clockworks Court • Container Yard • Crank Room • Drafting Office • Finishing Room • Gear Chamber • Kiln Room • Maintenance Hub • Movements • Pit Slide • Quarry • Roundhouse • Roundhouse Pit • Service Elevator • Storage Room • Storm Cellar • Synchro Gantry • Synchronization Room • Tomb • Transportation Hall • Warehouse • Workshop | |
| Secret Mine | Airway • Basin • Chalet • Chalet Approach • Cinder Mine • Coward's Chasm • Crossroads • Crystal Quarry • Deep Hall • Drift Hall • Frozen Pit • Fishing Hut • Gondola • High Wires • Ice Lake • Maintenance Room • Pit Mine • Prospector's Crossing • Shaft • Skip Slope • Smokehouse • Smuggler's Hideout • Terminal • Under the Ice • Workshop • Workshop Landing | |
| Treacherous Mansion | Ancient Exhibit • Archives • Aviation Exhibit • Bottom of Well • Ceremonial Chamber • Cliffside • Dark Age Exhibit • Dungeon Cells • East Balcony • East Corridor • East Gallery • Front Entrance • Gargoyle Roof • Grand East • Grand West • Guard Tunnel • Haunted Catacombs • Ice Age Exhibit • Inner Courtyard • Jungle Exhibit • Kitchen • Nautical Exhibit • Restrooms • Space Exhibit • Study • Terrace • Train Exhibit • Underground Lab • Veranda • West Balcony • West Corridor • West Gallery | |
| Other | Bunker • E. Gadd's Vault • King Boo's Illusion • Mario's Painting • ScareScraper • Toad's Painting | |
| Items | Items | Amethyst • Bill • Coin • Diamond • Emerald • Gem • Gold Bar • Gold Bone • Key • Poltergust 5000 • Red Coin • Ruby • Sapphire • Strobulb |
| Objects | Objects | Bulb (gold) • E-Gate • Paranormal portal • Paranormal shield • Sled-mounted shooter |
| Equipment | Dark-Light Device • Dual Scream • Pixelator • Poltergust 5000 • Strobulb | |
| Missions | Gloomy Manor | Poltergust 5000 • Gear Up • Quiet Please! • Visual Tricks • Sticky Situation • Confront the Source • Gradual Infiltration |
| Haunted Towers | A Job for a Plumber • The Pinwheel Gate • Graveyard Shift • Pool Party • Doggone Key • Tree Topping • Hostile Intrusion | |
| Old Clockworks | A Timely Entrance • Underground Expedition • Roundhouse Brawl • Play Catch • Piece at Last • Showtime • Outlandish Interruption | |
| Secret Mine | Cold Case • Hit Rock Bottom • Across the Chasm • Chilly Ride • Severe Infestation | |
| Treacherous Mansion | Front-Door Key • Double Trouble • A Train to Catch • Ambush Maneuver • Paranormal Chaos • Stop the Knightmare • Terrifying Invasion | |
| King Boo's Illusion | A Nightmare to Remember | |
| Further info | Further info | Gallery |