The Brainteasers are villains from Darkwing Duck. They are a group of hat-shaped alien criminals who attach themselves to someone's head, then control their every action. They feed on metal, which they must make the host eat. The only way to remove them is by making the host sneeze.
They have crash-landed on Earth after their ship is shot-down by the Girdist Revolutionaries, the good-guys from their planet. They decide to take over Earth, due to the heavy weaponry from the planet. They are defeated by Honker, who then become their sworn enemy, and also a hero on their home planet.
- Flarg the Terrible, Grand High Potentate of a Thousand Planets in the Delphnic Nebula: The green Brainteaser. He is the fearsome leader of the Brainteasers. After his defeat by Honker, he becomes obssessed in defeating him and ruining his reputation; only to be bested by him the second time.
- Barada: The yellow Brainteaser. He is Flarg's right-hand but is actually afraid of him.
- Nikto: The blue Brainteaser. He is another of Flarg's henchmen, but thinks more of eating than anything else.
- Talaya: The yellow Brainteaser with a pink ribbon. She is a lover of Flarg who breaks him out of prison, wanting to become his queen. She only appears in "Revenge of the Return of the Brainteasers".