Duckens are a plastic multi-colored duck dolls with a segmented section in their torso, first introduced in Monster Rancher 2, where they are obtainable by feeding cup jellies to your monster, winning a special doll in the mail and obtaining the glue to put it together. The doll can then be combined with two other monsters to create a Ducken. They have reappeared in all games since then, except Monster Farm Online and Monster Farm Lagoon. They are known for eccentric attacks, using parts of their body as projectiles.
Ducken also appears in the anime series. He used to live up on a mountain with a community of other monsters, but Captain Ebony and his Mock troops took it over for Gali when Moo started his invasion. Ducken was the only one to stay behind and try to reclaim their homeland, and even though he's reluctant to help the Searchers when they arrive, Mocchi eventually convinces him to help through the power of friendship.