Stuffwell is a living suitcase invented by Professor E. Gadd in order to help the heroes find the Chaos Emeralds in the Pipe Maze. He has many sensors that can detect the Emerald's power and communicate with the professor. He has a habit of saying: "BACK TO ADVENTURE!" whenever he is done speaking. Stuffwell is very cautious and warns the others not to do anything impulsive. He tries his best to keep the group from fighting amongst one another, but characters like Shadow refuses to listen to him.

Stuffwell has always been mute in the official Mario material and in this series. So I'll let you decide what the voice should sound like