Professor Elvin Gadd

Professor Elvin Gadd is a recurring character the Mario series. He is an incredible inventor and the head of Gadd Science Inc. He speaks in an unrecognizable jumble of words and sounds when he talks to other characters. His name is a pun of Egad, an exclamation.

Luigi's Mansion
He made his first appearance in Luigi's Mansion, in which he introduces Luigi to the problem of the ghosts in the mansion and gives him the Poltergust 3000 to enable him to rescue his brother, Mario.

Super Mario Sunshine
The professor has another fairly minor role in the story of Super Mario Sunshine, where E. Gadd invents the F.L.U.D.D. for Mario's use in cleaning up Isle Delfino, which was caused when Shadow Mario obtained the professor's magic paintbrush.

Mario & Luigi: Superstar Saga
In Mario & Luigi: Superstar Saga, he is the owner of the Starbeans Cafe in Beanbean Kingdom. If Mario collects enough beans for the coffee maker, he would test the coffee and give his inventions to Mario, one at a time.

Mario & Luigi: Partners in Time
In Mario & Luigi: Partners in Time, he is the inventor of the time machine that led to the capture of Princess Peach. The younger E. Gadd can be found in the past, after helping him he said something about going to a haunted mansion in Boo Woods.

Mario Party 6
E. Gadd also has a stage, E. Gadd's Garage, in Mario Party 6.

Non-Mario appearances
Professor E. Gadd makes a cameo in The Legend of Zelda: Wind Waker as one of Tetra's puzzle pieces.

Inventions
Gadd Science Inc. has developed many inventions and tools over the years. Among which are:
 * Poltergust 3000 - A high powered vacuum used to suck up ghosts, which Luigi uses
 * F.L.U.D.D. - The Flash Liquidizer Ultra Dousing Device. A water cannon with Artificial Intelligence, which Mario uses.
 * Magic Paintbrush - A tool Shadow Mario used to frame Mario by painting graffiti all over Isle Delfino.
 * The Game Boy Horror - A parody of the "Game Boy Color", this was a machine that had a map Luigi could use to navigate the mansion.
 * Ghost Portrificationizer - The Ghost Portrificationizer is a large machine which works in conjunction with the Poltergust 3000. Certain ghosts captured can be entrapped in portraits to be hung in E. Gadd's gallery
 * Super Poltergust 3001 - An advanced version of a Poltergust 3000. It has the same functions as the Poltergust 3000, but is much larger thereby allowing it to be ridden on.
 * Time Machine - Used by Princess Peach to visit the past at the beginning of Mario & Luigi: Partners in Time. It is powered by the Cobalt Star.
 * DS Time Radar - A handheld device that bears a striking resemblance to a Nintendo DS used briefly by E. Gadd to find Princess Peach in Mario & Luigi: Partners in Time. It has the ability to pinpoint which time period someone is trapped in.
 * Hydrogush 4000 - A large water pump used in Mario & Luigi: Partners in Time. It's not portable like the F.L.U.D.D., but it does have a lot of power.
 * Stuffwell - An intelligent suitcase used by the Mario Bros. on their quest in Mario & Luigi: Partners in Time. Its purpose is to manage the brothers' inventory and display their current status.
 * Poltergust 4000 - The Poltergust 4000 of the vehicles used by Luigi in Mario Kart DS to race in. It is similar to the Super Poltergust 3001 and the Poltergust 3000.

Gallery
Professor I. Gidd