McFreaks are unusual animals living on Detention Island. McFist captured four of them for his McFreaks show. However, Randy breaks them out, and soon Randy returns them to Detention Island in "McFreaks".
Barnabutt is a brown creature with the face of a mandrill, two legs, and four colorful butts surrounding his head. He is able to shoot a sonic pulse from his butts.
Rondo is a mix between a brown bear head (with the top of the head being bald) and a purple octopus body with the tentacles.
The nine-arm snake is a blue-green snake with nine arms and orange-brown hair on his head. He It is quite capable with machinery, hotwiring and driving Slimovitz's Car, as well as piloting (but not being able to land) McFist's hovercraft.
The toucan shark is a mix between a red parrot head and a shark body. He is still able to fly, he has parrot legs, and he has sharp teeth in his beak. He is able to spit acid.