All Fictional Characters/Monsters, Inc.

Cast

 * Big Bird (from Sesame Street) as Sulley
 * Elmo (from Sesame Street) as Mike Wazowski
 * June (from Little Einsteins) as Boo
 * Captain Hook (from Jake and the Never Land Pirates) as Randall Boggs
 * Bowser (from Mario) as Mr. Waternoose
 * Zoe (from Sesame Street) as Celia Mae
 * Daisy (from Thomas and Friends) as Roz
 * Woody and Buzz Lightyear (from Toy Story) as Needleman and Smitty
 * Mr. Smee (from Jake and the Never Land Pirates) as Fungus
 * Oswald (from Oswald) as Yeti
 * Fozzie Bear (from Muppets) as Mr. Bile
 * Linda Flynn-Fletcher (from Phineas and Ferb) as Ms. Flint
 * Herry Monster (from Sesame Street) as George Sanderson
 * Scooter (from Muppets) as Jerry
 * Homestar Runner (from Homestar Runner) as Bob Peterson
 * Rizzo the Rat (from Muppets) as Charlie
 * Kermit the Frog (from Muppets) as Harley P. Gerson
 * Gonzo (from Muppets) as Harry "Bud" Lucky
 * Telly Monster (from Sesame Street) as Joe J.J. Ranft
 * Wilt (from Foster's Home for Imaginary Friends) as Nicholas "Lanky" Schmidt
 * Hamm (from Toy Story) as Claws Ward
 * Bugs Bunny (from Looney Tunes) as Ricky Plesuski
 * Chris Griffin (from Family Guy) as Rivera
 * Marzipan (from Homestar Runner) as Betty
 * Thomas (from Thomas and Friends) as Spike Jones
 * Mr. Bump (from The Mr. Men Show) as Waxford
 * Barney (from Barney and Friends) as Ted Pauley
 * Yolanda Rat, Tatooey Rat, Masterson Rat and Chester Rat (from Muppets) as CDA
 * Strong Sad (from Homestar Runner) as Chalooby
 * Coach Z (from Homestar Runner) as Sushi Chef
 * Mr. Happy (from The Mr. Men Show) as Tony
 * Papa Bear and Mama Bear (from Sesame Street) as Trailer Folk
 * Kent Brockman (from The Simpsons) as TV News Reporter
 * Joy, Sadness, Anger, Fear and Disgust (from Inside Out) as Children
 * Goby (from Bubble Guppies) as A Kid That Mike Entertained