Plains dwelling, herbivorous creature indigenous to Nui Spiridonia.
In size and ecological niche, similar to the terrestrial cow/oxen/bison/wildebeest. The creature actually resembles a giant armadillo with a blunt head, dark, near black hide and armored shell, and a cluster of short tendrils around the mouth to pull in food. Rolleroxen have no eyes and instead use sonar to perceive their environment. They move using their legs for short distances. For more extended travel, they actually curl up into a ball and roll across the plains of their world, using their sonar to navigate.