Mudcrawlers are large fish-like creatures that are found in the rivers of Pandora in the Western Frontier. While they live predominantly underwater, they are able to hold their breath and climb onto land for extended periods of time.

They have muscular fins and a layer of mucus across their body, which allow them to crawl, climb, and slither across Pandoran riverbeds. When out of the water, the Mudcrawlers use their sensitive tendrils to track the smells and vibrations of small creatures. Once found, they use their large jaws to catch and eat their prey.

Beyond hunting, Mudcrawlers periodically return to the surface to lay their eggs, which they bury deep in the mud. Once hatched, the young must crawl into the river while being stalked by larger predators.