Professor Elvin Gadd, otherwise known as E. Gadd, is the mostly known scientist in the Mushroom Kingdom, known for creating machinery like the set of Poltergusts, Robo Mario, Gooigi and even helped with the partial creation of Project Model DGA.
When he's not dealing with paranormal activities, he's working on his simulation project, capable of bringing life to digital characters and sending characters in and out of new worlds.
His experiments tend to work correctly on the first try, but sometimes...
FUN FACTS
E. Gadd & Luigi get on well due to the various ventures regarding haunted mansions!
He's well versed in the world of the paranormal. Sometimes, he even gets ghosts to help him with his experiments!... as long as King Boo isn't around.
Mario's not his only test subject! He had the help of a toad named Solve with his simulations, though a mistake in the programming lead to them being trapped inside. He hasn't heard of them since.