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.
- Bearoar - A black bear with the snout of a wild boar.
- Buppy - An adorable little 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 chimpanzee that wears a turtle's shell.
- 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, and a rubber ball-like nose.
- 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.
- Gatorhopper - A grasshopper 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.
- Horskunk - A mutated skunk with a horse's head.
- 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.
- 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 his back.
- Snailfly - A hybrid snail with fly wings and legs.
- Snaketure - A snake mutant that has a vulture's head, wings and neck ruff.
- Squark - A shark modified to have a squirrel's legs, teeth and tail.
- Walark - Another 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 she 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. She will try to eat any other mutant. In one episode, Peri tried to make her fit into society.