Luigi's Mansion: Dark Moon Cheats - 3DS

Unlock Bonus Missions
Gradual Infiltration - Capture all 5 Boos in "Gloomy Manor".
Hostile Intrusion - Capture all 5 Boos in "Haunted Towers".
Outlandish Interruption - Capture all 5 Boos in "Old Clockworks".
Severe Infestation - Capture all 3 Boos in "Secret Mine".
Terrifying Invasion - Capture all 5 Boos in "Treacherous Mansion".

Unlock E. Gadd Medals
#1 - Complete the Dark Moon Quest mode.
#2 - Obtain a 3 star rank on every mission in the Dark Moon Quest mode.
#3 - Collect every type of ghost in game. (Both Evershade Valley and Scarescraper Ghosts).

Unlock Endless Floors in the Scarescraper
Hunter Endless - Beat a Hunter mode in a 25F Scarescraper, then "Create a Scarescraper".
Polterpup Endless - Beat a Polterpup mode in a 25F Scarescraper, then "Create a Scarescraper".
Rush Endless - Beat a Rush mode in a 25F Scarescraper, then "Create a Scarescraper".
Surprise Endless - Beat a Surprise mode in a 25F Scarescraper, then "Create a Scarescraper".

Unlock Scarescraper Mode
Beat the mission "Visual Tricks" in Gloomy Manor.

Unlock Vault Statues
Luigi statue - Collect all the gems in the Gloomy Manor.

Unlock Surprise Mode
Beat the single-player campaign, then select the Scarescraper option from E. Gadd's bunker to unlock this mode.