PeriVoiced by Rob Stefaniuk
An overly-optimistic mutant who has no actual knowledge of his purpose in life or what he's spliced from, yet yearns to find out.
- All-Loving Hero: Considers Joe a great guy even though their interactions mostly consist of Joe stepping on him (literally), is the only mutant who doesn't hate Smarty Smarts and actually seems to like him, is always quick to forgive Entree for even the worst mistakes, and even once tried to befriend the Wunny Sharbit, who generally terrifies everyone (for good reason)-and it worked. For a few minutes at least.
- Cartoon Creature: As mentioned above, his species is unknown. He looks very similar to Octocat however.
- Crouching Moron, Hidden Badass: Peri can shape-shift, detach his limbs, and turn people into his slaves with butterfly wings.
- Desperately Looking for a Purpose in Life: The pilot had Peri finding the Doctor's notebook after completely trashing his abandoned laboratory, which contained a diagram of Peri along with specifications below, possibly explaining his true intent in life. Peri and Entrée were both illiterate, and Entrée ended up using it as toilet paper when they did find someone who could read by the end of the episode.
- Fat and Skinny: The skinny to Entrée's fat.
- Funny Animal
- Grotesque Cute
- Heterosexual Life-Partners: With Entrée.
- Lethal Chef: In the first episode, he tried to make Entrée a sandwich. It ended up as some kind of sandwich-spider hybrid thing. With tentacles. That could fly.
- Line-of-Sight Name: "Peri" is the only part of the phrase "Failed Experiment Number Thirteen" (what he's really called) that actually sounds like a name.
- Only Sane Man: At least compared to Entrée, and sometimes to Joe.
- Overly Long Tongue: "Stuck Together" shows Peri to have one so long that he can use it to walk on.
- The Pollyanna
- Ridiculously Cute Critter
EntréeVoiced by Joe Pingue
Peri's best friend; a combination of a chicken, cow, shrimp, and a pig who was designed to be the ultimate eating animal, who's basically a bottomless pit with an attitude problem.
- Animal Gender Bender: He has an udder which produces milk. Apparently he also lays eggs.
- Big Eater: Entrée is one of the better examples, where even his own stomach got tired of his obsessive habits of literally eating everything he sees. He actually tried to eat own goddamn house once.
- Crouching Moron, Hidden Badass: Entrée can fly, teleport, mind-control people, and summon sea creatures to do his bidding.
- The Ditz
- Fat Bastard
- Funny Animal
- Grotesque Cute
- I Call Him "Mr. Happy": Entrée has named the teats on his udder. Except for one...
Peri: But what about that one?
*cue ominous thunder*
- Large Ham... Cow... Chicken... Shrimp Thing
- Let's Meet the Meat: Invoked repeatedly with Entrée, who seems to be aware that he was made to be food.
Peri: Stop! Entrée's not for eating!
Entrée: Well, actually...
- Poisonous Friend: Towards Peri.
- Trademark Favorite Food: Mayonnaise.
- Won The Superpower Lottery: He doesn't use them often, but in various gags he's been shown to have the powers of flight, teleportation, mind-control, Super Strength enough to drag entire islands through the ocean, and telekinesis.
Two-Legs Joe and Lord Wingus EternumVoiced by Patrick McKenna and Tom McCamus, respectively
A short-tempered two-legged rhinoceros with a small bird attached to his rear end. (Until it was revealed that the bird's name (well, his nickname that is) was Lord Wingus Eternum; a Zen master who was once banished by his peers for never removing the growth on his foot that has always interrupted his studies, which grew into Joe).
- Authority Equals Ass Kicking: As the mayor, Joe's only effective act of discipline is stomping until the victim changes to another state of matter.
- Awesome Mc Cool Name/Name That Unfolds Like Lotus Blossom: Lord Wingus Eternum.
- Badass: Two-Legs Joe and Lord Wingus Eternum are an amalgam of powers: The former has many varied kinds of Stomp powers that can affect the elements, reality, and even time and space, while the latter has psychic abilities from his species that allows him to fire eye-lasers, create energy shields that can protect the both of them, and can 'borrow minds'. He also creates ALL the flashbacks on the island. Since most problems are solved with Joe's stomping, Wingus stays quiet unless he's REALLY needed. Also, his desk/podium can turn into a hot rod-like vehicle in emergencies.
- Hair-Trigger Temper: Joe.
- Red Oni, Blue Oni: Two-Legs is the red, Wingus the blue.
- Team Dad: Two-Legs.
- Toothy Bird: Wingus.
- Ultimate Authority Mayor: Guess who.
PatriciaVoiced by Katie Crown
An intelligent non-mutated platypus who usually feels out of place from all the other inhabitants due to her being the only non-mutant character on the island. Could be quite violent when provoked.
Princess Pony ApehandsVoiced by Kedar Brown
A gorilla-pony with the uncanny personality of a six-year-old girl. She does demostrate her ungodly size and incomprehensible strength quite well,like walking through solid structures like it was made out of toilet paper.
CompuhorseVoiced by Patrick McKenna
A horse cyborg who, once a normal horse, was involuntarily merged with computer parts from a freak hardware factory explosion. Thanks to his new-found intelligence and ability to speak via voice programming, he can explain the wild phenomena the other characters somehow crossed paths with.
Fuzzy SnuggumsVoiced by Julie Lemieux
A cute and lovable critter who lives and breathes the urge to explore the island and the outside world, but could never do it right due to Karma having him blacklisted on Facebook.
Mister Smarty SmartsVoiced by Mike Kiss
An antagonistic, somewhat "knowledgeable", larger-than-life dolphin-chimpanzee who constantly attempts to subdue the townsfolk into doing his bidding and changing the island into an imperialistic "him-topia". Too bad his plans always backfire from either being thwarted by the protagonists, or that it's anything except being fool-proof.
OctocatVoiced by Katie Crown
A (you guessed it) cat-octopus who accompanies Mister Smarty Smarts with his plans to dominate and take over the island. Always speaks in meows.