Most of season four's episodes featured musical numbers to capitalize on Jason Alexander's Broadway success.
When Jason Alexander first signed up to play the title character, he thought he signed up for a one-off role. Because of this, he thought it would be fine to give Duckman a voice very different from his. While he loved doing the show, he reportedly came very close to damaging his voice; and because of this, he didn't reprise his role in the 1997 PC Adventure game, Duckman (1997).
Cornfed's deadpan, Joe Friday-esque voice came about as a happy accident. Voice actor Gregg Berger was not able to be with the rest of the cast during the initial recording sessions for the first half of the first season, as he was in Russia filming Loucademia de Polícia 7: Missão Moscou (1994) so had to record his lines over the phone, resulting in very his character's deadpan delivery, which the producers fell in love with.
In the opening credits of the Nicktoon, Ahhh! Monstros (1994) Ickis scares a toddler sitting on a training toilet will hiding inside of a boot. Next to the toddler is a toy wooden duck. The duck's head is that of Duckman. This was an Easter Egg since both shows were Klasky-Csupo produced and premiered in the same year.