From Muppet Wiki

Characters and alter-egos assumed by Gonzo in Muppet productions.

Picture	Name	Production	Notes
	Dearth Nadir	The Muppet Show	The villain of Star Wars (sort of) invaded the Swinetrek in episode 402, and kidnapped Chewbacca in episode 417.
	The Black Knight	The Muppet Show episode 305	Gonzo plays a knight who jousts with Floyd in a Camelot number.
	The Sheriff of Nottingham	The Muppet Show episode 323	Gonzo plays the bad guy in an adaptation of Robin Hood. He was also seen as the character in illustrated form in Jocelyn Stevenson's book, Robin Hood.
	a mummy	The Muppet Show episode 516	Gonzo sings "Night and Day" with some mummies and sarcophagi.
	Wizard Gonzo	Muppet Madness	Gonzo appeared in a wizard's outfit in Muppet Madness and in a number of Muppets comic strips. This was one of Guy and Brad Gilchrist's more unique contributions to the strip, as Gonzo never performed magic or wore that outfit, except in The Muppet Show Tour.
	Oznog	The Jim Henson Hour	Gonzo's mirror double from outer space (pictured on the far right), only seen once on the first episode of The Jim Henson Hour.
	Charles Dickens	The Muppet Christmas Carol	Gonzo in period garb as the 19th century novelist.
	Satyr	Muppet Classic Theater	Gonzo with goat-legs and horns as a wish-granting creature in the story of King Midas.
	Rumpelstiltskin	Muppet Classic Theater	Gonzo as the strange man with the long name, which is not Ralph Lauren.
	The Boy Who Cried Wolf	Muppet Classic Theater
	a bat	Muppets Tonight episode 108	Gonzo is costumed appropriately for a role in his own musical, "Bats."
	Cabin Boy Gonzo	Muppet Treasure Island	Gonzo, faithful friend to Jim Hawkins, lived in 18th century Bristol, England.
	Dr. Nose	Spy Muppets: License to Croak	Criminal mastermind and spoof of the James Bond villain Dr. No.
	Noseferatu	Muppet Monster Adventure	Gonzo is transformed into a vampire in Muppet Monster Adventure.
	Tin Thing	The Muppets' Wizard of Oz	A robot version of the Tin Woodman from The Wizard of Oz.