Mudhorns are a species of large monotreme, i.e. egg-laying mammal, that are native to the planet Arvala-7, though specimen can now be found on many worlds. The mudhorn’s heavy body slopes down in both directions from its shoulder hump, which may reach two hundred twenty centimetres in height. The animal’s squat body can reach a length of four metres, including a short tail. The mudhorn’s broad head is dominated by a long curving nasal horn which can reach a length of one point five metres and be forty centimetres across at its base and terminates in a sharp tip, which the animals keep sharpened by rubbing the edges on rocks and trees. Their bodies are covered in coarse brown fur up to twenty centimetres in length, which is frequently tangled and grimy due to their preference for damp, muddy surroundings. This combination of mud-covered coat and large horn give the animal their common name.

Mudhorns have large eyes on the sides of their head, but relatively poor eyesight. They depend more on their senses of hearing and smell. They are normally relatively placid animals expect when aroused to anger by threats toward themselves or their eggs. These eggs are ovoid, approximately forth centimetres top to bottom and thirty centimetres in diameter. They are filled with a thick, creamy orange yellow yolk, which is prized as a food by Jawas, so much so that they will forego a trove of ship parts in order to obtain one. Mudhorns lay one egg at a time, at intervals of about two years and nurse the hatchling for a year before fully weaning them. Adult mudhorns graze on marsh grasses, herbs and ferns, grinding them up with their large, flat teeth. A single animal can consume up to a hundred kilogrammes of vegetation a day in order to maintain their large bodies. Adults have few if any natural enemies due to their sheer size and dangerous disposition when threatened.