The Dum-Dum is a vicious species that Mental discovered while on an expedition. The creature was on the brink of extinction because it had eaten all of the species on the planet it was on and was slowly starving to death. Mental, seeing their potential, decided to take the Dum-Dums and use them for his own purposes. As a part of Mental's army, they serve as low-ranking troops.A flying variant of the Dum-Dum called the Tweetle Dum-Dum exists. It is the same as the regular Dum-Dum, but it flies via a beanie hat and will try to smack the target instead of biting it.