This is a list of all the different types of mutants on Spliced! who call Keep-Away Island their home. They are organized in alphabetical order. They are usually seen as background characters.
- Aardeater: This mutant has brown fur, the body, legs and ears of an aardvark, and the tail and nose of a giant anteater.
- Alligaturtle: An alligator that was genetically modified to have two legs and the shell of a turtle.
- Allopotamus: An Allosaurus mutant that has the nose and hind legs of a hippo. It most likely has the same creation origins as the Radioactive Dinosaur-Spider.
- Batdrill: A bat mutant that has the face of a proboscis monkey (mandrill).
- Bearoar: A black bear with the snout of a wild boar.
- Buppy: An adorable little puppy dog with a bat's wings.
- Camelephant: This mutant has an elephant's head for a body, a camel head and neck in place of a trunk, and camel legs with elephant feet.
- Carear: Another bear mutant with a carp's head and tail, four squid tentacles, and a reef shark's dorsal fin.
- Cassoeon: A cassowary that has a rhea's legs, a victroia crowned pigeon's head, a vulture's neck ruff and a marine iguana's tail and front legs.
- Caterpillar: Simply a large blue caterpillar with a cat's head.
- Chimpturtle: A turtle that has a chimp's arms and legs.
- Crocowolf: A wolf that has a crocodile's face. In the opening sequence, one eats the main characters then spits them out.
- Dobbit: A rabbit mutant that has a ring of dark fur around one eye, long, floppy dog-like ears, a rubber ball-like nose and a long tail.
- Dogfish: Not a shark, but a goldfish with a schnauzer's head.
- Duckzelle: A duck with a gazelle's hind legs.
- Flying Flog: A mutant that has a frog's head, a flying fish's pectoral fins, a horse's body and hind legs, and a skunk's tail.
- Gatoroach: A cockroach with an alligator's head.
- Gircow: A cow with a giraffe's neck, spots, and ossicones.
- Goosaroo: A kangaroo mutant that has a goose's head.
- Hippobear: The third bear mutant, this one with a hippo's head.
- Horsquirrel: A mutated squirrel with a horse's head and cloven feet.
- Kangaraccoon: Another kangaroo mutant that wears boxing gloves and has a raccoon's tail and eye rings.
- Lorisoon: A slender loris that has a raccoon's tail and eye rings.
- Macawlope: A macaw mutant with an antelope's ears, horns and legs.
- Molester: A small hamster mutant with a mole's eyes and nose. (note: this only has 2 syllables, the 'o' is long and the 'e' is silent)
- Moouse: A mouse with the antlers of a moose.
- Newtoad: A large toad with a newt's tail.
- Puffalo: This mutant resembles an ordinary bison, but can inflate like a puffer fish. A herd of them was seen in an ending short.
- Radioactive Dinosaur-Spider: A giant mutated Tyrannosaurus with six spider legs (one eye on each of the middle legs), huge venomous fangs, and a head with eight eyes. It is possible that the doctor created it by the method seen in Jurassic Park, or he used a time machine to capture a T-rex.
- Roosyile: A chicken mutant with the head of a komodo dragon.
- Sharkroach: A cockroach with four legs that has a shark's dorsal fin on its back.
- Snailfly: A hybrid snail with fly wings and legs.
- Snaketure: A snake mutant that has a vulture's head, wings and neck ruff.
- Spideraffe: The largest of all mutants, it's a giraffe with six legs and a furry spider body.
- Squark: A squirrel modified to have a hammerhead shark's head and dorsal fin.
- Walark: A mutated shark with a walrus' head.
- Whirrel: A large mutant squirrel with a orca's colouring and blowhole. In one episode, Entree's brain was switched with that of a Whirrel he was treating badly.
- Wunny Sharbit: The most dangerous mutant of all time, this rabbit has a great white shark's teeth that spin like the blade of a chainsaw. It will try to eat any other mutant. In one episode, Peri tried to make it fit into society.