Professor Elvin Gadd (Professor Oya Mā[ad] in Japan), more commonly known as E. Gadd, is a scientist who, with his various inventions, helps Luigi save his brother Mario and the mansion. His name is a pun on the Japanese interjection Oyamā![ae], meaning "Good heavens!" His name is also inspired by Nintendo game designer Yoshiyuki Oyama. The English translations accordingly adapted the name to a pun on the expression "egad"! His first appearance was in Luigi's Mansion for Nintendo GameCube, in which he investigates a haunted mansion that mysteriously appeared by his laboratory. To help him study the ghosts in the mansion, he uses the "Poltergust 3000", a high-powered vacuum cleaner that can suck in and capture ghosts, and the "Game Boy Horror", an invention for tracking and detecting objects such as Boos. He lends it to Luigi and helps him on his quest. His voice is played by Kazumi Totaka, who also voiced Yoshi. He reprises his supporting role in Luigi's Mansion: Dark Moon in a remodeled lab to assist Luigi again with his "Poltergust 5000" and a "Dual Scream", which replaces the Game Boy Horror. The Nintendo 3DS remake of the original Luigi’s Mansion introduces a new invention: a lime-green doppelgänger of Luigi, called "Gooigi", which can be brought along as a partner in local co-op play. In the third installment, Luigi's Mansion 3, Gooigi returns and E. Gadd provides Luigi with a new Poltergust model, the "Poltergust G-00".