Gus is one of the forgotten cartoons of Wasteland. In Epic Mickey, he accompanies Mickey Mouse as his guide in restoring Wasteland and defeating the Phantom Blot. In "Oswald's Story," he builds Oswald a remote control that shoots electrical beams in case he would need it for special defense, especially from the Mad Doctor...

While Bob Joles gave him grunting noises for Epic Mickey, it was Cary Elwes who provided the speaking voice for Gus in the sequel. He seems to have the voice of an old inventor or professor from England. I would say his voice is the opposite of Yen Sid's in terms of tonal quality as it sounds much higher than the sorcerer's. I would recommend looking up the cutscenes from Epic Mickey 2 and hear exactly what he sounds like to give the character the exact tone and accent.