Fat Cat is usually accompanied by four henchmen. In spite of their combined stupidity, Fat Cat almost always sends them out to do his dirty work for him, as he is too smart, or lazy to dirty his paws himself.
- Wart, a lizard, who dresses in a gangster-style suit and hat similar to his boss. Out of all of the henchmen, he is probably the least unintelligent and will sometimes ask questions about his boss' scheme, to which Fat Cat will usually explain in a gracious way, despite how simple he thinks he is. He was voiced by Jim Cummings.
- Mole, slow witted but cheerful, this overweight mole wears an undersized red t-shirt and a yellow hat. When plans go wrong, Mole usually is the one who Fat Cat chooses to use as a punching bag. In these instances, Fat Cat is harshly critical of Mole (in fact he just might be the most criticized member of the gang). He was voiced by Corey Burton.
- Mepps, a thin alley cat with brown and creme colored fur, who dresses in a ratty blue vest and toboggan who speaks with a whiny voice. Due to Mepps' bandaged tail and bitten ear, it is possible that Mepps has had many adventures. Whether of not these adventures involve Fat Cat and the rest of the gang is unknown. He was voiced by Peter Cullen.
- Snout, a rat that wears a short sleeved red turtle neck with a black vest and a dark blue hat that covers his eyes. It is possible the Snout joined the gang after the rangers formed and initially defeated Fat Cat because unlike Mole and Mepps, who appear in 16 episodes, and Wart, who appears in 15, Snout only appears in 7. He was voiced by Corey Burton.
Characters: Spunky | Cheddarhead Charlie and Camembert Kate | Tammy | Conrad Cockatoo | Sergeant Spinelli | Officer Kirby and Officer Muldoon | Colonel | Professor | Foxglove | Humphrey the Bear | Kookoo and Boots | Nemo | Spirit of the Lamp | Harry | Harriet | Hiram the Mummy | Clyde Cosgrove | Sir Colby | Tom | Darby Spree | Pop Top | Queenie | The Pi-Rats
Villains: Fat Cat | Fat Cat's Gang | Maltese de Sade | Le Sewer and Ratatouille | Professor Norton Nimnul | Robot Dogs | Billy the Squid | Sewernose de Bergerac | Banshee | Rat Capone | Arnold Mousenegger and Sugar Ray Lizard | Spy Rats | The Greatest Spy in the World | Captain Finn | All Hands and Mr. Starfish | Lahwhinie | Louie | Crocodile | El Emenopio | Winifred | Bud | Lou | Jack and Nickels | Desiree D'Allure | Erol | Baby Thaddeus | Monrovia and Pomona | Kismet | Mr. Dumpty | Nog | Cruiser and Bruiser | Bubbles | Irwina Allen
Locations: Professor Nimnul's Lab Dome
Disney Parks: Gadget's Go Coaster