One-Time Characters

• 
  Allosaurus (story arc)
• 
  Amazon Girl
• Amy
• 
  Ape
• 
  Armadillo

• Bat
• 
  Bat-Webbed Booger Being
• 
  Bath Foam
• 
  Bed Cover Monster
• 
  Binky Betsy
• 
  Black-and-White Drawing of Calvin
• 
  Bloatoid
• 
  Blob of gelatinous muck
• Blor-Utar
• 
  Box Office Cashier
• 
  Bug Being
• 
  Bug-like carcass

• 
  Calvin as a Doctor
• 
  Calvin as a Helmeted Super Hero
• 
  Calvin as an Astronaut
• 
  Calvin as Susie's Husband
• 
  Calvin Controllers
• 
  Calvin in 2-D Form
• 
  Calvin in Black-and-White Form
• 
  Calvin in Chemically Induced Invisible Form
• 
  Calvin in Dog Form
• Calvin in Drawing Form
• 
  Calvin in Film Negative Form
• 
  Calvin in Fire Form
• 
  Calvin in Frankenstein Monster Form
• 
  Calvin in Inch-Tall Form
• 
  Calvin in Mutant Fly Form
• 
  Calvin in Notebook Paper Form
• 
  Calvin in Plane Form
• 
  Calvin in Quarter-Inch Form
• 
  Calvin in Slinky Form
• 
  Calvin in Superhero Form
• 
  Calvin in Swollen Form
• 
  Calvin in Tiger Form
• 
  Calvin in Tiger Form (Transmogrifier alter ego)
• 
  Calvin in Twofold Insect-Sized Form
• 
  Calvin in Unexplained Giant Form
• 
  Calvin in Unexplained Invisible Form
• 
  Calvin in Werewolf Form
• 
  Calvin in Whaler Form
• 
  Calvin of the Future
• 
  Calvin the Ant
• 
  Calvin the Bold
• 
  Calvin the C-Bomb
• 
  Calvin the Criminal
• 
  Calvin the Elephant
• 
  Calvin the Flea
• 
  Calvin the God
• 
  Calvin the Human Light Particle
• 
  Calvin the Human Satellite
• 
  Calvin the Hummingbird
• 
  Calvin the Lightning Bolt
• 
  Calvin the Reptile
• 
  Calvin the Zombie
• 
  Calvin with Life of Pizzazz
• 
  Calvin's Good Side
• 
  Calvin's grandfather
• 
  Calvin's grandmother
• 
  Calvin's Skeleton
• 
  Calvin's Stomach Microbes
• 
  Calvin's Unethicated Duplicates
• 
  Candace
• 
  Captain Napalm (Alter ego)
• 
  Chameleon
• 
  Charlie (barber)
• 
  Chicken (Transmogrifier Gun alter ego)
• 
  Claire
• 
  Communicating Alien
• 
  Conversing aliens
• 
  Crab Teacher
• 
  Crocodile

• 
  Doofus Ignoramus
• 
  Dragon
• 
  Dream Makers
• 
  Duck

• 
  Eagle
• 
  Elephant (Transmogrifier alter ego)
• 
  Extra duplicate
• Extras

• 
  Farmer Brown
• 
  Filthy Rich
• 
  Firefighters
• First Husband
• 
  Florist
• 
  Flower (Transmogrifier Gun alter ego)
• 
  Frank
• 
  Fred
• 
  Frog
• 
  Frog (Transmogrifier alter ego)

• 
  Giant Amoeba
• 
  Giraffe
• 
  Grocery Store Cashier
• 
  Gurl
• 
  Gym Instructor

• 
  Hideous Blob
• Hobbes' Dad

• 
  Jessica

• Light Particle (Transmogrifier Gun alter ego)
• 
  Living X-Ray

• Mabel Syrup
• 
  Maggot-Man
• 
  Maurice
• 
  Megalon
• 
  Miss Wormwood in Plesiosaur Form
• 
  Moe's friend
• 
  Monster (Alter ego)
• 
  Motherly alien
• 
  Mr. Kneecapper
• 
  Mrs. Carroll
• 
  Mt. Calvin

• 
  Naggon
• 
  Nollij

• 
  Other motherly alien
• 
  Owl

• 
  Photographer
• 
  Pig
• 
  Planet Calvin
• 
  Polka-dotted alien
• 
  Pteranodon
• 
  Pterodactyl

• 
  Raccoon
• 
  Reclining alien
• 
  Ronald
• 
  Russy White

• 
  Safari Al
• 
  Safe (Transmogrifier Gun alter ego)
• 
  Scavenger Mordon
• 
  School Alter Egos
• 
  Shark
• 
  Slug
• 
  Snow Goons
• 
  Song Sparrow
• 
  Susie as President of the United States
• 
  Susie in Adult Form as a Patient
• Susie's father
• 
  Susie's mother

• 
  The Bog Monster
• 
  The Incredibly Annoying Human Echo
• 
  The World's Most Powerful Computer
• Tommy
• 
  Tommy Chesnutt
• 
  Tornado

• 
  Uncle Max
• 
  Unidentified Alien Abducters
• 
  Unnamed Pterosaur

• 
  Whale
• 
  Winslow
• 
  Woman at the Zoo
• 
  Wonga-Taa

• 
  X-387 Robot Probe

• 
  Yukbarf

• 
  Zarch
• 
  Zarg
• 
  Zargon
• 
  Zokk (alien)
• 
  Zondarg
• 
  Zorkon