The Christmas Dumbo Octopus is an event Dumbo Octopus, first released as part of the 2016 Christmas Event, but available year-round in the Christmas Tank.
The Christmas Dumbo Octopus is, essentially, a Dumbo Octopus in a Santa costume. Its skin is the same color as the Dumbo Octopus, although most of it is covered in a red suit. Its face is visible through a large hole in the suit surrounded by white fluff, and a small, golden bell hangs directly below its mouth. On top of its head, there are two white, fluffy balls, one on either side. Curiously, its eyes are partially obscured by the fluff around the suit's face-hole.
In the 2016 Christmas Event (when it was released), the player must create 3 Christmas Football Fish, and purchase the Christmas Dumbo Octopus for 3000 event currency. After that event was finished, players must obtain the Christmas Dumbo Octopus by, when in the Christmas Tank, owning the Happy House on the Hill, creating three Christmas Event Seahorses, and owning 35 total Christmas Event fish.