Paddywhack is a supernatural entity who inhabits a haunted jack-in-the-box. Although he is capable of possessing inanimate objects and imbuing them with his will, he can and will sometimes appear in his true form, which is a very tall, thin duck with long legs, red eyes and sharp teeth, wearing a black and white leotard with a ruffled collar. Paddywhack feeds off of negative emotions and always exhorts others to "Please play with me!", enticing them to join him in his various acts of mayhem.
At some point, Paddywhack became trapped in his jack-in-the-box, which was unknowingly put on display at a toy exhibit in a St. Canard museum. Quackerjack robbed the exhibit, stealing the box, but ultimately decided it was worthless and threw it aside, thus releasing Paddywhack. The evil spirit possessed Quackerjack's doll, Mr. Banana Brain, and proceeded to run rampant throughout St. Canard, causing mischief.
He was eventually stopped by Darkwing Duck, who, with Quackerjack's help, used positive emotions to weaken Paddywhack and re-imprison him inside of the jack-in-the-box, which Darkwing then threw into the Audubon Bay. However a large fish swallowed the box, and Paddywhack, escaping once again, and possessed the fish.
Paddywhack is voiced by Phil Hartman.