Name: Professor Elvin Gadd
Role: Head of Gadd Science Incorporated
Fave Food: Pickled dandelions marinaded in diesel oil
Fave School Subject: Science
Fave Item: Poltergust 3000
Fave Minion: Orange Ghost (because they're easy to capture)

Prof Gadd first appeared in Luigi's Mansion, where he made what is probably his most important role of all as he is the one who supplies Luigi with what he needs to rescue Mario from the Mansion. Without Gadd Mario would still be trapped in the mansion now and Luigi would have to fight on his own.

Although Prof Gadd didn't appear in Super Mario Sunshine, his inventions were very important. Prof Gadd supplied Bowser Jr with his ultimate weapon, the paintbrush Jr. could use to unleash some kind of attack, but the main invention of Gadd's here is the FLUDD, which Mario surely couldn't have gone without.

In Mario & Luigi: Superstar Saga, Gadd is not that important but does provide the kingdom with a way of getting rid of useless beans and raising stats at the same time. Also many of the inventions here give the Mario Bros. the power they need to beat tough enemies easily, and all this is done just by his inventions.

In Mario Party 4 Gadd doesn't appear nor play an important role, but does put the useful item Gaddlight in the item shops.